Selective delivery molecules and methods of use

ABSTRACT

Disclosed herein is a selective delivery molecule comprising: (a) an acidic sequence (portion A) which is effective to inhibit or prevent the uptake into cells or tissue retention, (b) a molecular transport or retention sequence (portion B), and (c) a linker between portion A and portion B, and (d) at least one cargo moiety.

CROSS-REFERENCES

This application is a continuation of U.S. application Ser. No.15/806,246, field on Nov. 7, 2017, which is a continuation of U.S.application Ser. No. 15/295,482, filed Oct. 17, 2016, now issued as U.S.Pat. No. 9,840,537 on Dec. 12, 2017, which is a continuation of U.S.application Ser. No. 15/132,773, filed Apr. 19, 2016, now issued as U.S.Pat. No. 9,504,763 on Nov. 29, 2016, which is a continuation of U.S.application Ser. No. 15/006,832, filed Jan. 26, 2016, now issued as U.S.Pat. No. 9,371,367 on Jun. 21, 2016, which is a continuation of U.S.application Ser. No. 14/235,522, filed on Sep. 18, 2014, now issued asU.S. Pat. No. 9,278,144 on Mar. 8, 2016, which is the National Stageentry of International Application No. PCT/US2012/048732 filed on Jul.27, 2012, which claims priority to U.S. Provisional Patent ApplicationNo. 61/513,287, titled “Selective Delivery Molecules and Methods of Use”and filed Jul. 29, 2011, the disclosures of which are incorporatedherein by reference in their entireties.

SEQUENCE LISTING

The instant application contains a Sequence Listing which has beensubmitted electronically in ASCII format and is hereby incorporated byreference in its entirety. Said ASCII copy, created on Dec. 20, 2018, isnamed “39088708305_SL.txt” and is 10,877 bytes in size.

SUMMARY OF THE INVENTION

Disclosed herein, in certain embodiments, are selective deliverymolecule of Formula I, having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a macromolecule; and    -   D_(A) and D_(B) are each independently selected from an imaging        agent and a therapeutic; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, the number of        basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence RLQLKL (SEQ ID NO: 11). In        some embodiments, X comprises the amino acid sequence RLQLK(Ac)        (SEQ ID NO: 12) (SEQ ID NO: 12). In some embodiments, M is        selected from a protein, a natural polymer, a synthetic polymer,        or a dendrimer. In some embodiments, M is selected from dextran,        a PEG polymer, albumin, or a combination thereof. In some        embodiments, M is a PEG. In some embodiments, M is selected from        PEG 5 kDa, PEG 12 kDa, PEG 20 kDa, PEG 30 kDa, and PEG40 kDa. In        some embodiments, D_(A) and D_(B) are a pair of acceptor and        donor fluorescent moieties that are capable of undergoing        Försters/fluorescence resonance energy transfer with the other.        In some embodiments, D_(A) and D_(B) are Cy5 and Cy7. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye750. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye800. In some        embodiments, D_(A) and D_(B) are Cy5 and ICG. In some        embodiments, D_(A) and D_(B) are a fluorescent moiety and a        fluorescence-quenching moiety. In some embodiments, the molecule        of Formula I is: SDM-14, SDM-15, SDM-23, SDM-24, SDM-25, SDM-26,        SDM-27, SDM-32, or SDM-35.

Disclosed herein, in certain embodiments, are selective deliverymolecules of Formula I, having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are each independently an imaging agent; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, the number of        basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence PPRSFL (SEQ ID NO: 10). In        some embodiments, X comprises the amino acid sequence RLQLKL        (SEQ ID NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, D_(A) and D_(B) are a fluorescent        moiety and a fluorescence-quenching moiety. In some embodiments,        the molecule of Formula I is: SDM-14, SDM-15, SDM-23, SDM-24,        SDM-25, SDM-26, SDM-27, SDM-32; or SDM-35.

Disclosed herein, in certain embodiments, are molecules of Formula II,having the structure:

A₁-X₁-B₁;   Formula II

wherein,

-   -   X₁ is a cleavable linker;    -   A₁ is a peptide with a sequence comprising 5 to 9 acidic amino        acids and having a first reactive amino acid moiety c_(A);    -   B₁ is a peptide with a sequence comprising 7 to 9 basic amino        acids and having a second reactive amino acid moiety c_(B); and    -   A₁-X₁-B₁ has a third reactive amino acid moiety c_(M) on A₁ or        X₁; and        wherein c_(A) is capable of reacting with a first cargo moiety        comprising D_(A), c_(B) is capable of reacting with a second        cargo moiety comprising D_(B), and c_(M) is capable of reacting        with a macromolecular carrier comprising M to form a molecule of        Formula I.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, the c_(A),        c_(B), and c_(M) have functional groups that are orthogonally        reactive. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine.

Disclosed herein, in certain embodiments, are tissue samples comprisinga molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)];   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are each independently an imaging agent; and        wherein [c_(M)-M] is bound at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, the tissue sample is a pathology slide or        section. In some embodiments, the tissue sample is cancerous. In        some embodiments, the cancerous tissue is: breast cancer tissue,        colon cancer tissue, squamous cell carcinoma tissue, prostate        cancer tissue, melanoma tissue, or thyroid cancer tissue. In        some embodiments, the cancerous tissue is breast cancer tissue.        In some embodiments, the cancerous tissue is colon cancer        tissue. In some embodiments, A and B do not have an equal number        of acidic and basic amino acids. In some embodiments, the number        of basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence PPRSFL (SEQ ID NO: 10). In        some embodiments, X comprises the amino acid sequence RLQLKL        (SEQ ID NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, D_(A) and D_(B) are a fluorescent        moiety and a fluorescence-quenching moiety. In some embodiments,        the molecule of Formula I is: SDM-14, SDM-15, SDM-23, SDM-24,        SDM-25, SDM-26, SDM-27, SDM-32, and SDM-35.

Disclosed herein, in certain embodiments, are methods of delivering apair of imaging agents to a tissue of interest, comprising contactingthe tissue of interest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)];   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are each independently an imaging agent; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, the tissue of interest is cancerous. In        some embodiments, the cancerous tissue is: breast cancer tissue,        colorectal cancer tissue, squamous cell carcinoma tissue,        prostate cancer tissue, melanoma tissue, and thyroid cancer        tissue. In some embodiments, the cancerous tissue is breast        cancer tissue. In some embodiments, the cancerous tissue is        colon cancer tissue. In some embodiments, A and B do not have an        equal number of acidic and basic amino acids. In some        embodiments, the number of basic amino acids in B is greater        than the number of acidic amino acids in A. In some embodiments,        A is a peptide comprising 5 or 9 consecutive glutamates (SEQ ID        NO: 3). In some embodiments, B is a peptide comprising 8 or 9        consecutive arginines (SEQ ID NO: 4). In some embodiments, A is        a peptide comprising 5 or 9 consecutive glutamates (SEQ ID        NO: 3) and B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 consecutive glutamates (SEQ ID NO: 5) and B is a        peptide comprising 8 consecutive arginines (SEQ ID NO: 6). In        some embodiments, c_(A), c_(B), and c_(M) are each independently        a 0-1 amino acid. In some embodiments, c_(A), c_(B), and c_(M)        are each independently selected from a naturally-occurring amino        acid or a non-naturally-occurring amino acid. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from a D amino acid, a L amino acid, an α-amino acid, a        β-amino acid, or a γ-amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence PPRSFL (SEQ ID NO: 10). In        some embodiments, X comprises the amino acid sequence RLQLKL        (SEQ ID NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, D_(A) and D_(B) are a fluorescent        moiety and a fluorescence-quenching moiety. In some embodiments,        the molecule of Formula I is: SDM-14, SDM-15, SDM-23, SDM-24,        SDM-25, SDM-26, SDM-27, SDM-32, and SDM-35.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising:

(a) administering to the individual a molecule of Formula I thatlocalizes to the tissue of interest in the individual,

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)];   Formula I

-   -   wherein,        -   X is a cleavable linker;        -   A is a peptide with a sequence comprising 5 to 9 acidic            amino acids;        -   B is a peptide with a sequence comprising 7 to 9 basic amino            acids;        -   c_(A), c_(B), and c_(M) each independently comprise 0-1            amino acid;        -   M is a polyethylene glycol (PEG) polymer; and        -   D_(A) and D_(B) are each independently an imaging agent; and    -   wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B; and        (b) visualizing at least one of the imaging agents.        In some embodiments, the tissue is cancerous. In some        embodiments, the cancerous tissue is: breast cancer tissue,        colorectal cancer tissue, squamous cell carcinoma tissue,        prostate cancer tissue, melanoma tissue, or thyroid cancer        tissue. In some embodiments, the cancerous cell or tissue is        breast cancer tissue. In some embodiments, the cancerous cell or        tissue is colon cancer tissue. In some embodiments, the method        further comprises surgically removing the tissue of interest        from the individual. In some embodiments, the surgical margin        surrounding the tissue of interest is decreased. In some        embodiments, the method further comprises preparing a tissue        sample from the removed cell or tissue of interest. In some        embodiments, the method further comprises staging the cancerous        tissue. In some embodiments, A and B do not have an equal number        of acidic and basic amino acids. In some embodiments, the number        of basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence PPRSFL (SEQ ID NO: 10). In        some embodiments, X comprises the amino acid sequence RLQLKL        (SEQ ID NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, the method further comprises        visualizing Försters/fluorescence resonance energy transfer        between D_(A) and D_(B). In some embodiments, D_(A) and D_(B)        are a fluorescent moiety and a fluorescence-quenching moiety. In        some embodiments, the molecule is chosen from: SDM-14, SDM-15,        SDM-23, SDM-24, SDM-25, SDM-26, SDM-27, SDM-32, and SDM-35.

Disclosed herein, in certain embodiments, are selective deliverymolecules of Formula I, having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)];   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 or 9 consecutive        glutamates (SEQ ID NO: 3);    -   B is a peptide with a sequence comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, c_(A), c_(B),        and c_(M) are each independently a 0-1 amino acid. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from any amino acid having a free thiol group, any        amino acid having a N-terminal amine group, and any amino acid        with a side chain capable of forming an oxime or hydrazone bond        upon reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, X comprises        the amino acid sequence RPLALWRS (SEQ ID NO: 7). In some        embodiments, D_(A) and D_(B) are Cy5 and Cy7. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye750. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye800. In some        embodiments, D_(A) and D_(B) are Cy5 and ICG.

Disclosed herein, in certain embodiments, are selective deliverymolecules of Formula I, having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)];   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 consecutive        glutamates (SEQ ID NO: 5);    -   B is a peptide with a sequence comprising 8 consecutive        arginines (SEQ ID NO: 6);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from any amino acid having a free thiol        group, any amino acid having a N-terminal amine group, and any        amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, X comprises        the amino acid sequence RPLALWRS (SEQ ID NO: 7). In some        embodiments, D_(A) and D_(B) are Cy5 and Cy7. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye750. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye800. In some        embodiments, D_(A) and D_(B) are Cy5 and ICG.

Disclosed herein, in certain embodiments, are selective deliverymolecules of Formula I, having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)];   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 9 consecutive        glutamates (SEQ ID NO: 13);    -   B is a peptide with a sequence comprising 9 consecutive        arginines (SEQ ID NO: 14);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from any amino acid having a free thiol        group, any amino acid having a N-terminal amine group, and any        amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, X comprises        the amino acid sequence RPLALWRS (SEQ ID NO: 7). In some        embodiments, D_(A) and D_(B) are Cy5 and Cy7. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye750. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye800. In some        embodiments, D_(A) and D_(B) are Cy5 and ICG.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-14.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-15.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-23.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-24.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-25.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-26.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-27.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-32.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-35.

Disclosed herein, in certain embodiments, are peptides according toPeptide P-3.

FIGURES

FIG. 1 exemplifies the effects of a selective delivery molecule (SDM) byshowing whole mouse fluorescence images of 3 different mice injectedwith SDM-6. The images were taken 2 hours after injection. The tumor andcontra-lateral tissue used to calculate the contrast are indicated onthe right hand mouse. The mean contrast for the three mice is 1.1.

FIG. 2 exemplifies ratiometric fluorescence changes of selectivedelivery molecules. In this figure, SDM-9 was cleaved with with 1 nMMMP-2 enzyme. The increase of donor (left panel) and decrease inacceptor (right panel) fluorescence is indicative of decreased FRETafter peptide cleavage.

FIG. 3 exemplifies fluorescence enhancement of selective deliverymolecules after protease cleavage. SDM-10 was cleaved with 1 nM MMP-9enzyme in buffered saline. The Cy5 fluorescence increases >100 foldafter peptide cleavage because the quencher dyes is no longerintramolecularly attached to Cy5 and it can no longer efficiently quenchCy5.

FIG. 4 exemplifies fluorescence enhancement of selective deliverymolecule SDM-10 upon cleavage by tumor homogenates. Selective deliverymolecule 10 (SDM-10) was cleaved with HT-1080 tumor homogenates. 1 nMMMP-9 or 10 uL tumor tissue homogenates (TH2 and TH3) were mixed with 1uM compound 13 in 100 uL buffer for 24 h at 37° C. GM6001 is a generalbroad spectrum inhibitor of MMPs. The control lane contains SDM-6 whichis highly fluorescent in the intact, uncleaved form which runs at thetop of the gel. Uncleaved SDM-10 is nonfluorescent due to efficientquenching (second column from left). After cleavage by MMP-9 thefragment containing the fluorophore is dequenched (becoming highlyfluorescent) and runs near the bottom of the gel. As demonstrated in thegel, tumor homogenates also cleave SDM-10 to generate the highlyfluorescent product. This reaction is blocked by the MMP inhibitorindicating that the cleavage is due to tumor associated MMPs.

FIG. 5 exemplifies the bio-distribution of 3 fluorescent compounds 6hours after IV tail vein administration of 2.9 nmol of each compound.SDM-6 has 5-fold higher tissue distribution into tumor compared to SDM-1and SDM-2. Selective delivery molecules 1 and 2 have equal numbers ofglutamates and arginines giving them a net neutral core while SDM-6 hasa net 3+ charge due to more positively charged arginines.

FIG. 6 exemplifies application of emission ratio imaging of FRET todetermine the presence of cancer in mouse lymph nodes. An emission ratioimage was generated using equation 2 where Exp1=0.7 sec, Exp2=4.1 secand k=20. The right hand panel show the ratio image which show highcontrast between the metastatic lymph node (very large node indicatedwith lower left dark arrow) and the non-metastatic nodes (other arrows).The higher ratio is shown as lighter pixels (metastatic) compared todarker lower ratio pixels for the non-metastic nodes.

FIG. 7 exemplifies results from an ex vivo mouse tissue activity assay.SDM-23 was incubated with activated tumor and normal thigh muscle tissuehomogenates. Enzymatic activity from the tissues resulted in SDM-23cleavage and generated a large FRET emission ratio increase (labeledprimary tumor). The ratio increase was the result of SDM cleavage.Normal muscle tissue showed no cleavage activity of SDM-23.

FIG. 8 exemplifies FRET emission ratio data an ex vivo human tissueassay. SDM-25 was incubated with normal human breast and cancerous humanbreast tissue (WD2808, WD2821, WD2815, WD2817, WD2824) homogenates.Enzymatic activity and SDM-25 cleavage was found to be significantlygreater in cancerous human breast tissue compared to normal human breasttissue (data bar with errors).

FIG. 9 exemplifies FRET emission ratio data from an ex vivo human tissueassay. SDM-25 and SDM-32 were incubated with normal healthy human breast(WD2823) and cancerous human breast tissue (WD2808, WD2815). Enzymaticactivity and SDM cleavage was found to be greater in cancerous humanbreast tissue compared to normal human breast tissue.

FIG. 10 exemplifies a scatter plot of FRET emission ratio data ofpositive and negative lymph nodes from a mouse metastatic lymph nodemodel that have been treated with SDM-24. Nodes were assigned to beeither positive or negative based on analysis of H&E staining by apathologist.

FIG. 11 exemplifies a ROC curve generated by changing the thresholdvalue used to assign either a positive or negative metastatic predictionfrom emission ratio data using SDM-24 in metastatic lymph node model.This data show high sensitivity and specificity for diagnosing cancerousand non-cancerous lymph nodes.

DETAILED DESCRIPTION OF THE INVENTION

Selective delivery molecules (SDMs) allow the targeted delivery oftherapeutic agents and/or imaging agents to specific cells and/ortissues. In some embodiments, selective delivery molecules comprise (a)a molecular transport or retention sequence (portion B), (b) at leastone cargo moiety (portion D) bound to portion A, B, or X, (c) X alinker, and (d) a macromolecular carrier and (e) an acidic sequence(portion A) which is effective to inhibit or prevent the uptake intocells or tissue retention. In some embodiments, cleavage of X linker,which allows the separation of portion A from portion B, is effective toallow the uptake or retention of portion B and the attached cargo intocells and tissue. However, selective delivery molecules may be subjectto rapid pharmacokinetic clearance with short plasma half-life, broaddistribution, and slow wash out from multiple non-target tissues withnon-specific uptake. Thus, there is a need for a selective deliverymolecule with increased in vivo circulation, accumulation in targettissue relative to non-target tissue, modulated extravasationselectivity, and modulated bio-distribution. For imaging agents, thereis a need for increased contrast in target tissue relative to backgroundtissue.

Certain Definitions

As used herein, the following terms have the meanings ascribed to themunless specified otherwise.

As used herein, the term “targeting molecule” refers to any agent (e.g.,peptide, protein, nucleic acid polymer, aptamer, or small molecule) thatassociates with (e.g., binds to) a target of interest. The target ofinterest may be a tissue, a cell, a cellular structure (e.g., anorganelle), a protein, a peptide, a polysaccharide, or a nucleic acidpolymer. In some embodiments, the targeting molecule is any agent thatassociates with (e.g., binds to) one or more cancer cells of a subject.

The terms “polypeptide,” “peptide” and “protein” are usedinterchangeably herein to refer to a polymer of amino acid residues. Theterms apply to naturally occurring amino acid polymers as well as aminoacid polymers in which one or more amino acid residues is anon-naturally occurring amino acid (e.g., an amino acid analog). Theterms encompass amino acid chains of any length, including full lengthproteins (i.e., antigens), wherein the amino acid residues are linked bycovalent peptide bonds. As used herein, the terms “peptide” refers to apolymer of amino acid residues typically ranging in length from 2 toabout 50 residues. In certain embodiments the peptide ranges in lengthfrom about 2, 3, 4, 5, 7, 9, 10, or 11 residues to about 50, 45, 40, 45,30, 25, 20, or 15 residues. In certain embodiments the peptide ranges inlength from about 8, 9, 10, 11, or 12 residues to about 15, 20 or 25residues. Where an amino acid sequence is provided herein, L-, D-, orbeta amino acid versions of the sequence are also contemplated as wellas retro, inversion, and retro-inversion isoforms. Peptides also includeamino acid polymers in which one or more amino acid residues is anartificial chemical analogue of a corresponding naturally occurringamino acid, as well as to naturally occurring amino acid polymers. Inaddition, the term applies to amino acids joined by a peptide linkage orby other modified linkages (e.g., where the peptide bond is replaced byan α-ester, a β-ester, a thioamide, phosphonamide, carbamate,hydroxylate, and the like (see, e.g., Spatola, (1983) Chem. Biochem.Amino Acids and Proteins 7: 267-357), where the amide is replaced with asaturated amine (see, e.g., Skiles et al., U.S. Pat. No. 4,496,542,which is incorporated herein by reference, and Kaltenbronn et al.,(1990) Pp. 969-970 in Proc. 11th American Peptide Symposium, ESCOMScience Publishers, The Netherlands, and the like)).

The term “amino acid” refers to naturally occurring and synthetic aminoacids, as well as amino acid analogs and amino acid mimetics thatfunction in a manner similar to the naturally occurring amino acids.Naturally occurring amino acids are those encoded by the genetic code,as well as those amino acids that are later modified, e.g.,hydroxyproline, γ-carboxyglutamate, and O-phosphoserine. Amino acidanalogs refers to compounds that have the same basic chemical structureas a naturally occurring amino acid, i.e., an α carbon that is bound toa hydrogen, a carboxyl group, an amino group, and an R group, e.g.,homoserine, norleucine, methionine sulfoxide. Such analogs have modifiedR groups (e.g., norleucine) or modified peptide backbones, but retainthe same basic chemical structure as a naturally occurring amino acid.Amino acid mimetics refers to chemical compounds that have a structurethat is different from the general chemical structure of an amino acid,but that functions in a manner similar to a naturally occurring aminoacid. Amino acids are either D amino acids of L amino acids.

Amino acids may be referred to herein by either their commonly knownthree letter symbols or by the one-letter symbols recommended by theIUPAC-IUB Biochemical Nomenclature Commission. Nucleotides, likewise,may be referred to by their commonly accepted single-letter codes.

One of skill will recognize that individual substitutions, deletions oradditions to a peptide, polypeptide, or protein sequence which alters,adds or deletes a single amino acid or a small percentage of amino acidsin the encoded sequence is a “conservatively modified variant” where thealteration results in the substitution of an amino acid with achemically similar amino acid. Conservative substitution tablesproviding functionally similar amino acids are well known in the art.Such conservatively modified variants are in addition to and do notexclude polymorphic variants, interspecies homologs, and alleles of theinvention.

As used herein, the term “label” refers to a molecule that facilitatesthe visualization and/or detection of a targeting molecule disclosedherein. In some embodiments, the label is a fluorescent moiety.

The phrase “specifically binds” when referring to the interactionbetween a targeting molecule disclosed herein and a target (e.g.,purified protein, cancer cells or cancerous tissue, tumor, or metastaticlesion, metastases, or lymph node or metastatic lymph node), refers tothe formation of a high affinity bond between the targeting molecule andthe target. Further, the term means that the targeting molecule has lowaffinity for non-targets.

“Selective binding,” “selectivity,” and the like refers to thepreference of an agent to interact with one molecule as compared toanother. Preferably, interactions between a targeting molecule disclosedherein and a target are both specific and selective. Note that in someembodiments an agent is designed to “specifically bind” and “selectivelybind” two distinct, yet similar targets without binding to otherundesirable targets

The terms “individual,” “patient,” or “subject” are usedinterchangeably. As used herein, they mean any mammal (i.e. species ofany orders, families, and genus within the taxonomic classificationanimalia: chordata: vertebrata: mammalia). In some embodiments, themammal is a human. None of the terms require or are limited to situationcharacterized by the supervision (e.g. constant or intermittent) of ahealth care worker (e.g. a doctor, a registered nurse, a nursepractitioner, a physician's assistant, an orderly, or a hospice worker).

The terms “administer,” “administering”, “administration,” and the like,as used herein, refer to the methods that may be used to enable deliveryof agents or compositions to the desired site of biological action.These methods include, but are not limited to parenteral injection(e.g., intravenous, subcutaneous, intraperitoneal, intramuscular,intravascular, intrathecal, intravitreal, infusion, or local).Administration techniques that are optionally employed with the agentsand methods described herein, include e.g., as discussed in Goodman andGilman, The Pharmacological Basis of Therapeutics, current ed.;Pergamon; and Remington's, Pharmaceutical Sciences (current edition),Mack Publishing Co., Easton, Pa.

The term “pharmaceutically acceptable” as used herein, refers to amaterial that does not abrogate the biological activity or properties ofthe agents described herein, and is relatively nontoxic (i.e., thetoxicity of the material significantly outweighs the benefit of thematerial). In some instances, a pharmaceutically acceptable material maybe administered to an individual without causing significant undesirablebiological effects or significantly interacting in a deleterious mannerwith any of the components of the composition in which it is contained.

The term “surgery” as used herein, refers to any method that may be usedto investigate, manipulate, change, or cause an effect in a tissue by aphysical intervention. These methods include, but are not limited toopen surgery, endoscopic surgery, laparoscopic surgery, minimallyinvasive surgery, robotic surgery, and any procedures that may affect acancerous tissue such as tumor resection, cancer tissue ablation, cancerstaging, cancer diagnosis, lymph node staging, sentinel lymph nodedetection, or cancer treatment.

The term “guided surgery” as used herein, refers to any surgicalprocedure where the surgeon employs an imaging agent to guide thesurgery.

The term “cancer” as used herein, refers to any disease involvinguncontrolled growth or proliferation cellsin the human body. Cancers mayfurther be characterized by the ability of cells to migrate from theoriginal site and spread to distant sites (i.e., metastasize). Cancersmay be sarcomas, carcinomas, lymphomas, leukemias, blastomas, or germcell tumors. Cancers may occur in a variety of tissues including but notlimited to lung, breast, ovaries, colon, esophagus, rectum, bone,prostate, brain, pancreas, bladder, kidney, liver, blood cells, lymphnodes, and stomach.

Selective Delivery Molecules

Disclosed herein, in certain embodiments, are selective deliverymolecule of Formula I, having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a macromolecule; and    -   D_(A) and D_(B) are each independently selected from an imaging        agent and a therapeutic; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, the number of        basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence RLQLKL (SEQ ID NO: 11). In        some embodiments, X comprises the amino acid sequence RLQLK(Ac)        (SEQ ID NO: 12). In some embodiments, M is selected from a        protein, a natural polymer, a synthetic polymer, or a dendrimer.        In some embodiments, M is selected from dextran, a PEG polymer,        albumin, or a combination thereof. In some embodiments, M is a        PEG. In some embodiments, M is selected from PEG 5 kDa, PEG 12        kDa, PEG 20 kDa, PEG 30 kDa, and PEG40 kDa. In some embodiments,        D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other. In some embodiments,        D_(A) and D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and        D_(B) are Cy5 and IRDye750. In some embodiments, D_(A) and D_(B)        are Cy5 and IRDye800. In some embodiments, D_(A) and D_(B) are        Cy5 and ICG. In some embodiments, D_(A) and D_(B) are a        fluorescent moiety and a fluorescence-quenching moiety. In some        embodiments, the molecule of Formula I is: SDM-14, SDM-15,        SDM-23, SDM-24, SDM-25, SDM-26, SDM-27, SDM-32, or SDM-35.

Disclosed herein, in certain embodiments, are selective deliverymolecules of Formula I, having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are each independently an imaging agent; and    -   wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, the number of        basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence PPRSFL (SEQ ID NO: 10). In        some embodiments, X comprises the amino acid sequence RLQLKL        (SEQ ID NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, D_(A) and D_(B) are a fluorescent        moiety and a fluorescence-quenching moiety. In some embodiments,        the molecule of Formula I is: SDM-14, SDM-15, SDM-23, SDM-24,        SDM-25, SDM-26, SDM-27, SDM-32; or SDM-35.

Disclosed herein, in certain embodiments, are selective deliverymolecules of Formula I, having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 or 9 consecutive        glutamates (SEQ ID NO: 3);    -   B is a peptide with a sequence comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, c_(A), c_(B),        and c_(M) are each independently selected from any amino acid        having a free thiol group, any amino acid having a N-terminal        amine group, and any amino acid with a side chain capable of        forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently a 0-1 amino acid. In        some embodiments, c_(A), c_(B), and c_(M) are each independently        selected from D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and Cy7.

Disclosed herein, in certain embodiments, are selective deliverymolecules of Formula I, having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 consecutive        glutamates (SEQ ID NO: 5);    -   B is a peptide with a sequence comprising 8 consecutive        arginines (SEQ ID NO: 6);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, X comprises        the amino acid sequence RPLALWRS (SEQ ID NO: 7). In some        embodiments, D_(A) and D_(B) are Cy5 and Cy7. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye750. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye800. In some        embodiments, D_(A) and D_(B) are Cy5 and ICG.

Disclosed herein, in certain embodiments, are selective deliverymolecules of Formula I, having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 9 consecutive        glutamates (SEQ ID NO: 13);    -   B is a peptide with a sequence comprising 9 consecutive        arginines (SEQ ID NO: 14);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of    -   undergoing Försters/fluorescence resonance energy transfer with        the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, X comprises        the amino acid sequence RPLALWRS (SEQ ID NO: 7). In some        embodiments, D_(A) and D_(B) are Cy5 and Cy7. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye750. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye800. In some        embodiments, D_(A) and D_(B) are Cy5 and ICG.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-14.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-15.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-23.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-24.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-25.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-26.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-27.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-32.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-35.

Disclosed herein, in certain embodiments, are peptides according toPeptide P-3.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-14.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-15.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-23.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-24.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-25.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-26.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-27.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-32.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-35.

Portion A

In some embodiments, A is a peptide with a sequence comprising 2 to 20acidic amino acids. In some embodiments, peptide portion A comprisesbetween about 2 to about 20 acidic amino acids. In some embodiments,peptide portion A comprises between about 5 to about 20 acidic aminoacids. In some embodiments, A has a sequence comprising 5 to 9 acidicamino acids. In some embodiments, A has a sequence comprising 5 to 8acidic amino acids. In some embodiments, A has a sequence comprising 5to 7 acidic amino acids. In some embodiments, A has a sequencecomprising 5 acidic amino acids. In some embodiments, A has a sequencecomprising 6 acidic amino acids. In some embodiments, A has a sequencecomprising 7 acidic amino acids. In some embodiments, A has a sequencecomprising 8 acidic amino acids. In some embodiments, A has a sequencecomprising 9 acidic amino acids.

In some embodiments, peptide portion A comprises between about 2 toabout 20 consecutive acidic amino acids. In some embodiments, peptideportion A comprises between about 5 to about 20 consecutive acidic aminoacids. In some embodiments, A has a sequence comprising 5 to 9consecutive acidic amino acids. In some embodiments, A has a sequencecomprising 5 to 8 consecutive acidic amino acids. In some embodiments, Ahas a sequence comprising 5 to 7 consecutive acidic amino acids. In someembodiments, A has a sequence comprising 5 consecutive acidic aminoacids. In some embodiments, A has a sequence comprising 6 consecutiveacidic amino acids. In some embodiments, A has a sequence comprising 7consecutive acidic amino acids. In some embodiments, A has a sequencecomprising 8 consecutive acidic amino acids. In some embodiments, A hasa sequence comprising 9 consecutive acidic amino acids.

In some embodiments, peptide portion A comprises between about 2 toabout 20 acidic amino acids selected from, aspartates and glutamates. Insome embodiments, peptide portion A comprises between about 5 to about20 acidic amino acids selected from, aspartates and glutamates. In someembodiments, A has a sequence comprising 5 to 9 acidic amino acidsselected from, aspartates and glutamates. In some embodiments, A has asequence comprising 5 to 8 acidic amino acids selected from, aspartatesand glutamates. In some embodiments, A has a sequence comprising 5 to 7acidic amino acids selected from, aspartates and glutamates. In someembodiments, A has a sequence comprising 5 acidic amino acids selectedfrom, aspartates and glutamates. In some embodiments, A has a sequencecomprising 6 acidic amino acids selected from, aspartates andglutamates. In some embodiments, A has a sequence comprising 7 acidicamino acids selected from, aspartates and glutamates. In someembodiments, A has a sequence comprising 8 acidic amino acids selectedfrom, aspartates and glutamates. In some embodiments, A has a sequencecomprising 9 acidic amino acids selected from, aspartates andglutamates.

In some embodiments, peptide portion A comprises between about 2 toabout 20 consecutive acidic amino acids selected from, aspartates andglutamates. In some embodiments, peptide portion A comprises betweenabout 5 to about 20 consecutive acidic amino acids selected from,aspartates and glutamates. In some embodiments, A has a sequencecomprising 5 to 9 consecutive acidic amino acids selected from,aspartates and glutamates. In some embodiments, A has a sequencecomprising 5 to 8 consecutive acidic amino acids selected from,aspartates and glutamates. In some embodiments, A has a sequencecomprising 5 to 7 consecutive acidic amino acids selected from,aspartates and glutamates. In some embodiments, A has a sequencecomprising 5 consecutive acidic amino acids selected from, aspartatesand glutamates. In some embodiments, A has a sequence comprising 6consecutive acidic amino acids selected from, aspartates and glutamates.In some embodiments, A has a sequence comprising 7 consecutive acidicamino acids selected from, aspartates and glutamates. In someembodiments, A has a sequence comprising 8 consecutive acidic aminoacids selected from, aspartates and glutamates. In some embodiments, Ahas a sequence comprising 9 consecutive acidic amino acids selectedfrom, aspartates and glutamates.

In some embodiments, peptide portion A comprises between about 2 toabout 20 glutamates. In some embodiments, peptide portion A comprisesbetween about 5 to about 20 glutamates. In some embodiments, A has asequence comprising 5 to 9 glutamates. In some embodiments, A has asequence comprising 5 to 8 glutamates. In some embodiments, A has asequence comprising 5 to 7 glutamates. In some embodiments, A has asequence comprising 5 glutamates. In some embodiments, A has a sequencecomprising 6 glutamates. In some embodiments, A has a sequencecomprising 7 glutamates. In some embodiments, A has a sequencecomprising 8 glutamates. In some embodiments, A has a sequencecomprising 9 glutamates.

In some embodiments, peptide portion A comprises between about 2 toabout 20 consecutive glutamates (SEQ ID NO: 15). In some embodiments,peptide portion A comprises between about 5 to about 20 consecutiveglutamates (SEQ ID NO: 16). In some embodiments, A has a sequencecomprising 5 to 9 consecutive glutamates (SEQ ID NO: 41). In someembodiments, A has a sequence comprising 5 to 8 consecutive glutamates(SEQ ID NO: 17). In some embodiments, A has a sequence comprising 5 to 7consecutive glutamates (SEQ ID NO: 18). In some embodiments, A has asequence comprising 5 consecutive glutamates (SEQ ID NO: 5). In someembodiments, A has a sequence comprising 6 consecutive glutamates (SEQID NO: 19). In some embodiments, A has a sequence comprising 7consecutive glutamates (SEQ ID NO: 20). In some embodiments, A has asequence comprising 8 consecutive glutamates (SEQ ID NO: 21). In someembodiments, A has a sequence comprising 9 consecutive glutamates (SEQID NO: 13).

In some embodiments, portion A comprises 5 consecutive glutamates (SEQID NO: 5) (i.e., EEEEE (SEQ ID NO: 5) or eeeee). In some embodiments,portion A comprises 9 consecutive glutamates (SEQ ID NO: 13) (i.e.,EEEEEEEEE (SEQ ID NO: 13) or eeeeeeeee).

An acidic portion A may include amino acids that are not acidic. Acidicportion A may comprise other moieties, such as negatively chargedmoieties. In embodiments of a selective delivery molecule disclosedherein, an acidic portion A may be a negatively charged portion,preferably having about 2 to about 20 negative charges at physiologicalpH that does not include an amino acid.

In some embodiments, the amount of negative charge in portion A isapproximately the same as the amount of positive charge in portion B. Insome embodiments, the amount of negative charge in portion A is not thesame as the amount of positive charge in portion B. In some embodiments,improved tissue uptake is seen in a selective delivery molecule whereinthe amount of negative charge in portion A is not the same as the amountof positive charge in portion B. In some embodiments, improvedsolubility is observed in a selective delivery molecule wherein theamount of negative charge in portion A is not the same as the amount ofpositive charge in portion B. In some embodiments, faster tissue uptakeis seen in a selective delivery molecule wherein the amount of negativecharge in portion A is not the same as the amount of positive charge inportion B. In some embodiments, greater tissue uptake is seen in aselective delivery molecule wherein the amount of negative charge inportion A is not the same as the amount of positive charge in portion B.

Portion A is either L-amino acids or D-amino acids. In embodiments ofthe invention, D-amino acids are preferred in order to minimizeimmunogenicity and nonspecific cleavage by background peptidases orproteases. Cellular uptake of oligo-D-arginine sequences is known to beas good as or better than that of oligo-L-arginines.

It will be understood that portion A may include non-standard aminoacids, such as, for example, hydroxylysine, desmosine, isodesmosine, orother non-standard amino acids. Portion A may include modified aminoacids, including post-translationally modified amino acids such as, forexample, methylated amino acids (e.g., methyl histidine, methylatedforms of lysine, etc.), acetylated Amino acids, amidated amino acids,formylated amino acids, hydroxylated amino acids, phosphorylated aminoacids, or other modified amino acids. Portion A may also include peptidemimetic moieties, including portions linked by non-peptide bonds andamino acids linked by or to non-amino acid portions.

The Selective Delivery Molecules disclosed herein are effective where Ais at the amino terminus or where A is at the carboxy terminus, i.e.,either orientation of the peptide bonds is permissible.

Portion B

In some embodiments, B is a peptide with a sequence comprising 5 to 15basic amino acids. In some embodiments, peptide portion B comprisesbetween about 5 to about 20 basic amino acids. In some embodiments,peptide portion B comprises between about 5 to about 12 basic aminoacids. In some embodiments, peptide portion B comprises between about 7to about 9 basic amino acids. In some embodiments, peptide portion Bcomprises between about 7 to about 8 basic amino acids. In someembodiments, peptide portion B comprises 9 basic amino acids. In someembodiments, peptide portion B comprises 8 basic amino acids. In someembodiments, peptide portion B comprises 7 basic amino acids.

In some embodiments, peptide portion B comprises between about 5 toabout 20 consecutive basic amino acids. In some embodiments, peptideportion B comprises between about 5 to about 12 consecutive basic aminoacids. In some embodiments, peptide portion B comprises between about 7to about 9 consecutive basic amino acids. In some embodiments, peptideportion B comprises between about 7 to about 8 consecutive basic aminoacids. In some embodiments, peptide portion B comprises 9 consecutivebasic amino acids. In some embodiments, peptide portion B comprises 8consecutive basic amino acids. In some embodiments, peptide portion Bcomprises 7 consecutive basic amino acids.

In some embodiments, peptide portion B comprises between about 5 toabout 20 basic amino acids selected from arginines, histidines, andlysines. In some embodiments, peptide portion B comprises between about5 to about 12 basic amino acids selected from arginines, histidines, andlysines. In some embodiments, peptide portion B comprises between about7 to about 9 basic amino acids selected from arginines, histidines, andlysines. In some embodiments, peptide portion B comprises between about7 to about 8 basic amino acids selected from arginines, histidines, andlysines. In some embodiments, peptide portion B comprises 9 basic aminoacids selected from arginines, histidines, and lysines. In someembodiments, peptide portion B comprises 8 basic amino acids selectedfrom arginines, histidines, and lysines. In some embodiments, peptideportion B comprises 7 basic amino acids selected from arginines,histidines, and lysines.

In some embodiments, peptide portion B comprises between about 5 toabout 20 consecutive basic amino acids selected from arginines,histidines, and lysines. In some embodiments, peptide portion Bcomprises between about 5 to about 12 consecutive basic amino acidsselected from arginines, histidines, and lysines. In some embodiments,peptide portion B comprises between about 7 to about 9 consecutive basicamino acids selected from arginines, histidines, and lysines. In someembodiments, peptide portion B comprises between about 7 to about 8consecutive basic amino acids selected from arginines, histidines, andlysines. In some embodiments, peptide portion B comprises 9 consecutivebasic amino acids selected from arginines, histidines, and lysines. Insome embodiments, peptide portion B comprises 8 consecutive basic aminoacids selected from arginines, histidines, and lysines. In some

In some embodiments, peptide portion B comprises between about 5 toabout 20 arginines. In some embodiments, peptide portion B comprisesbetween about 5 to about 12 arginines. In some embodiments, peptideportion B comprises between about 7 to about 9 arginines. In someembodiments, peptide portion B comprises between about 7 to about 8arginines. In some embodiments, peptide portion B comprises 9 arginines.In some embodiments, peptide portion B comprises 8 arginines. In someembodiments, peptide portion B comprises 7 arginines.

In some embodiments, peptide portion B comprises between about 5 toabout 20 consecutive arginines (SEQ ID NO: 22). In some embodiments,peptide portion B comprises between about 5 to about 12 consecutivearginines (SEQ ID NO: 23). In some embodiments, peptide portion Bcomprises between about 7 to about 9 consecutive arginines (SEQ ID NO:24). In some embodiments, peptide portion B comprises between about 7 toabout 8 consecutive arginines (SEQ ID NO: 25). In some embodiments,peptide portion B comprises 9 consecutive arginines (SEQ ID NO: 14). Insome embodiments, peptide portion B comprises 8 consecutive arginines(SEQ ID NO: 6). In some embodiments, peptide portion B comprises 7consecutive arginines (SEQ ID NO: 26).

A basic portion B may include amino acids that are not basic. Basicportion B may comprise other moieties, such as positively chargedmoieties. In embodiments, a basic portion B may be a positively chargedportion, preferably having between about 5 and about 20 positive chargesat physiological pH, that does not include an amino acid. In someembodiments, the amount of negative charge in portion A is approximatelythe same as the amount of positive charge in portion B. In someembodiments, the amount of negative charge in portion A is not the sameas the amount of positive charge in portion B.

Portion B is either L-amino acids or D-amino acids. In embodiments ofthe invention, D-amino acids are preferred in order to minimizeimmunogenicity and nonspecific cleavage by background peptidases orproteases. Cellular uptake of oligo-D-arginine sequences is known to beas good as or better than that of oligo-L-arginines.

It will be understood that portion B may include non-standard aminoacids, such as, for example, hydroxylysine, desmosine, isodesmosine, orother non-standard amino acids. Portion B may include modified aminoacids, including post-translationally modified amino acids such as, forexample, methylated amino acids (e.g., methyl histidine, methylatedforms of lysine, etc.), acetylated amino acids, amidated amino acids,formylated amino acids, hydroxylated amino acids, phosphorylated aminoacids, or other modified amino acids. Portion B may also include peptidemimetic moieties, including portions linked by non-peptide bonds andamino acids linked by or to non-amino acid portions.

In embodiments where X is a peptide cleavable by a protease, it may bepreferable to join the C-terminus of X to the N-terminus of B, so thatthe new amino terminus created by cleavage of X contributes anadditional positive charge that adds to the positive charges alreadypresent in B.

Conjugation Group (c)

In some embodiments, the cargo (e.g., D_(A) and D_(B)) and themacromolecule carriers (M) are attached indirectly to A-X-B.

In some embodiments, the cargo (e.g., D_(A) and D_(B)) and themacromolecule carriers (M) are attached indirectly to A-X-B by aconjugation group (c_(A), c_(B), and c_(M)). In some embodiments, thecargo (e.g., D_(A) and D_(B)) and the macromolecule carriers (M) areattached indirectly to A-X-B by a reactive conjugation group (c_(A),c_(B), and c_(M)). In some embodiments, the cargo (e.g., D_(A) andD_(B)) and the macromolecule carriers (M) are attached indirectly toA-X-B by an orthogonally reactive conjugation group (c_(A), c_(B), andc_(M)). In some embodiments, c_(A), c_(B), and c_(M) each independentlycomprise an amino acid. In some embodiments, c_(A), c_(B), and c_(M)each independently comprise 0-10 amino acids. In some embodiments,c_(A), c_(B), and c_(M) each independently comprise 1 amino acid. Insome embodiments, c_(A), c_(B), and c_(M) each independently comprise 2amino acids. In some embodiments, c_(A), c_(B), and c_(M) eachindependently comprise 3 amino acids. In some embodiments, c_(A), c_(B),and c_(M) each independently comprise 4 amino acids. In someembodiments, c_(A), c_(B), and c_(M) each independently comprise 5 aminoacids. In some embodiments, c_(A), c_(B), and c_(M) each independentlycomprise 6 amino acids. In some embodiments, c_(A), c_(B), and c_(M)each independently comprise 7 amino acids. In some embodiments, c_(A),c_(B), and c_(M) each independently comprise 8 amino acids. In someembodiments, c_(A), c_(B), and c_(M) each independently comprise 9 aminoacids. In some embodiments, c_(A), c_(B), and c_(M) each independentlycomprise 10 amino acids.

In some embodiments, c_(A), c_(B), and c_(M) each independently comprisea derivatized amino acid. In some embodiments, multiple cargos (D) areattached to a derivatized amino acid conjugation group.

In some embodiments, the conjugation group comprises a receptor ligand.

In some embodiments, c_(A), c_(B), and c_(M) each independently comprisea naturally-occurring amino acid or a non-naturally-occurring aminoacid. In some embodiments, c_(A), c_(B), and c_(M) each independentlycomprise from a D amino acid, a L amino acid, an α-amino acid, a ß-aminoacid, or a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M)each independently comprise any amino acid having a free thiol group,any amino acid containing a free amine group, any amino acid having aN-terminal amine group, and any amino acid with a side chain capable offorming an oxime or hydrazone bond upon reaction with a hydroxylamine orhydrazine group. In some embodiments, c_(A), c_(B), and c_(M) eachindependently comprise D-cysteine, D-glutamate, lysine, andpara-4-acetyl L-phenylalanine. In some embodiments, c_(B) comprises anyamino acid having a free thiol group. In some embodiments, c_(B)comprises D-cysteine. In some embodiments, c_(A) comprises any aminoacid having a N-terminal amine group. In some embodiments, c_(A)comprises D-glutamate. In some embodiments, c_(A) comprises lysine. Insome embodiments, c_(M) comprises any amino acid with a side chaincapable of forming an oxime or hydrazone bond upon reaction with ahydroxylamine or hydrazine group. In some embodiments, c_(M) comprisespara-4-acetyl L-phenylalanine.

In some embodiments, c_(A), c_(B), and c_(M) are each independentlyselected from a naturally-occurring amino acid or anon-naturally-occurring amino acid. In some embodiments, c_(A), c_(B),and c_(M) are each independently selected from a D amino acid, a L aminoacid, an α-amino acid, a β-amino acid, or a γ-amino acid. In someembodiments, c_(A), c_(B), and c_(M) are each independently any aminoacid having a free thiol group, any amino acid containing a free aminegroup, any amino acid having a N-terminal amine group, and any aminoacid with a side chain capable of forming an oxime or hydrazone bondupon reaction with a hydroxylamine or hydrazine group. In someembodiments, c_(A), c_(B), and c_(M) are each independently selectedfrom: D-cysteine, D-glutamate, lysine, and para-4-acetylL-phenylalanine. In some embodiments, c_(B) is any amino acid having afree thiol group. In some embodiments, c_(B) is D-cysteine. In someembodiments, c_(A) is any amino acid having a N-terminal amine group. Insome embodiments, c_(A) is D-glutamate. In some embodiments, c_(A) islysine. In some embodiments, c_(M) is any amino acid with a side chaincapable of forming an oxime or hydrazone bond upon reaction with ahydroxylamine or hydrazine group. In some embodiments, c_(M) ispara-4-acetyl L-phenylalanine.

Cargo (D) Imaging Agents

In some embodiments, an imaging agent is a dye. In some embodiments, animaging agent is a fluorescent moiety. In some embodiments, afluorescent moiety is selected from: a fluorescent protein, afluorescent peptide, a fluorescent dye, a fluorescent material or acombination thereof.

All fluorescent moieties are encompassed within the term “fluorescentmoiety.” Specific examples of fluorescent moieties given herein areillustrative and are not meant to limit the fluorescent moieties for usewith the targeting molecules disclosed herein.

Examples of fluorescent dyes include, but are not limited to, xanthenes(e.g., rhodamines, rhodols and fluoresceins, and their derivatives);bimanes; coumarins and their derivatives (e.g., umbelliferone andaminomethyl coumarins); aromatic amines (e.g., dansyl; squarate dyes);benzofurans; fluorescent cyanines; indocarbocyanines; carbazoles;dicyanomethylene pyranes; polymethine; oxabenzanthrane; xanthene;pyrylium; carbostyl; perylene; acridone; quinacridone; rubrene;anthracene; coronene; phenanthrecene; pyrene; butadiene; stilbene;porphyrin; pthalocyanine; lanthanide metal chelate complexes; rare-earthmetal chelate complexes; and derivatives of such dyes.

Examples of fluorescein dyes include, but are not limited to,5-carboxyfluorescein, fluorescein-5-isothiocyanate,fluorescein-6-isothiocyanate and 6-carboxyfluorescein.

Examples of rhodamine dyes include, but are not limited to,tetramethylrhodamine-6-isothiocyanate, 5-carboxytetramethylrhodamine,5-carboxy rhodol derivatives, tetramethyl and tetraethyl rhodamine,diphenyldimethyl and diphenyldiethyl rhodamine, dinaphthyl rhodamine,rhodamine 101 sulfonyl chloride (sold under the tradename of TEXASRED®).

Examples of cyanine dyes include, but are not limited to, Cy3, Cy3B,Cy3.5, Cy5, Cy5.5, Cy7, IRDYE680, Alexa Fluor 750, IRDye800CW, ICG.

Examples of fluorescent peptides include GFP (Green Fluorescent Protein)or derivatives of GFP (e.g., EBFP, EBFP2, Azurite, mKalamal, ECFP,Cerulean, CyPet, YFP, Citrine, Venus, YPet).

Fluorescent labels are detected by any suitable method. For example, afluorescent label may be detected by exciting the fluorochrome with theappropriate wavelength of light and detecting the resultingfluorescence, e.g., by microscopy, visual inspection, via photographicfilm, by the use of electronic detectors such as charge coupled devices(CCDs), photomultipliers, etc.

In some embodiments, the imaging agent is labeled with apositron-emitting isotope (e.g., ¹⁸F) for positron emission tomography(PET), gamma-ray isotope (e.g., ^(99m)Tc) for single photon emissioncomputed tomography (SPECT), or a paramagnetic molecule or nanoparticle(e.g., Gd³⁺ chelate or coated magnetite nanoparticle) for magneticresonance imaging (MRI).

In some embodiments, the imaging agent is labeled with: a gadoliniumchelate, an iron oxide particle, a super paramagnetic iron oxideparticle, an ultra small paramagnetic particle, a manganese chelate orgallium containing agent.

Examples of gadolinium chelates include, but are not limited todiethylene triamine pentaacetic acid (DTPA),1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), and1,4,7-triazacyclononane-N,N′,N″-triacetic acid (NOTA).

In some embodiments, the imaging agent is a near-infrared fluorophorefor near-infra red (near-IR) imaging, a luciferase (firefly, bacterial,or coelenterate) or other luminescent molecule for bioluminescenceimaging, or a perfluorocarbon-filled vesicle for ultrasound.

In some embodiments, the imaging agent is a nuclear probe. In someembodiments, the imaging agent is a SPECT or PET radionuclide probe. Insome embodiments, the radionuclide probe is selected from: a technetiumchelate, a copper chelate, a radioactive fluorine, a radioactive iodine,a indiuim chelate.

Examples of Tc chelates include, but are not limited to HYNIC, DTPA, andDOTA.

In some embodiments, the imaging agent contains a radioactive moiety,for example a radioactive isotope such as ²¹¹At, ¹³¹I, ¹²⁵I, ⁹⁰Y, ¹⁸⁶Re,¹⁸⁸Re, ¹⁵³Sm, ²¹²Bi, ³²P, ⁶⁴Cu radioactive isotopes of Lu, and others.

In some embodiments, a selective delivery molecule according to FormulaI comprising an imaging agent is employed in guided surgery. In someembodiments, the selective delivery molecule preferentially localized tocancerous, or other undesirable tissues (i.e. necrotic tissues). In someembodiments, a selective delivery molecule according to Formula Icomprising an imaging agent is employed in a guided surgery to removecolorectal cancer. In some embodiments, guided surgery employing theselective delivery molecule allows a surgeon to excise as little healthy(i.e., non-cancerous) tissue as possible. In some embodiments, guidedsurgery employing the selective delivery molecule allows a surgeon tovisualize and excise more cancerous tissue than the surgeon would havebeen able to excise without the presence of the selective deliverymolecule. In some embodiments, the surgery is fluorescence-guidedsurgery.

Therapeutic Agents

Disclosed herein, in certain embodiments, is the use of a selectivedelivery molecule disclosed herein for delivering a therapeutic agent toa tissue or a plurality of cells. In some embodiments, the therapeuticagent is an anti-inflammatory agent. In some embodiments, thetherapeutic agemt is an anti-cancer agent. In some embodiments, theselective delivery molecule is used to treat colorectal cancer.

In some embodiments, a D moiety is independently a therapeutic agent. Insome embodiments, the therapeutic agent is selected from: achemotherapeutic agent, a steroid, an immunotherapeutic agent, atargeted therapy, an anti-inflammatory agent, or a combination thereof.

In some embodiments, the therapeutic agent is a B cell receptor pathwayinhibitor. In some embodiments, the therapeutic agent is a CD79Ainhibitor, a CD79B inhibitor, a CD19 inhibitor, a Lyn inhibitor, a Sykinhibitor, a PI3K inhibitor, a Blnk inhibitor, a PLCγ inhibitor, a PKCβinhibitor, or a combination thereof. In some embodiments, thetherapeutic agent is an antibody, B cell receptor signaling inhibitor, aPI3K inhibitor, an IAP inhibitor, an mTOR inhibitor, aradioimmunotherapeutic, a DNA damaging agent, a proteosome inhibitor, ahistone deacytlase inhibitor, a protein kinase inhibitor, a hedgehoginhibitor, an Hsp90 inhibitor, a telomerase inhibitor, a Jak1/2inhibitor, a protease inhibitor, a PKC inhibitor, a PARP inhibitor, or acombination thereof. In some embodiments, the therapeutic agent isselected from: chlorambucil, ifosphamide, doxorubicin, mesalazine,thalidomide, lenalidomide, temsirolimus, everolimus, fludarabine,fostamatinib, paclitaxel, docetaxel, ofatumumab, rituximab,dexamethasone, prednisone, CAL-101, ibritumomab, tositumomab,bortezomib, pentostatin, endostatin, bendamustine, chlorambucil,chlormethine, cyclophosphamide, ifosfamide, melphalan, prednimustine,trofosfamide, busulfan, mannosulfan, treosulfan, carboquone, thiotepa,triaziquone, carmustine, fotemustine, lomustine, nimustine, ranimustine,semustine, streptozocin, etoglucid, dacarbazine, mitobronitol,pipobroman, temozolomide, methotrexate, permetrexed, pralatrexate,raltitrexed, cladribine, clofarabine, fludarabine, mercaptopurine,nelarabine, tioguanine, azacitidine, capecitabine, carmofur, cytarabine,decitabine, fluorouracil, gemcitabine, tegafur, vinblastine,vincristine, vindesine, vinflunine, vinorelbine, etoposide, teniposide,demecolcine, docetaxel, paclitaxel, paclitaxel poliglumex, trabectedin,dactinomycin, aclarubicin, daunorubicin, doxorubicin, epirubicin,idarubicin, mitoxantrone, pirarubicin, valrubicin, zorubincin,bleomycin, ixabepilone, mitomycin, plicamycin, carboplatin, cisplatin,oxaliplatin, satraplatin, procarbazine, aminolevulinic acid,efaproxiral, methyl aminolevulinate, porfimer sodium, temoporfin,dasatinib, erlotinib, everolimus, gefitinib, imatinib, lapatinib,nilotinib, pazonanib, sorafenib, sunitinib, temsirolimus, alitretinoin,altretamine, amzacrine, anagrelide, arsenic trioxide, asparaginase,bexarotene, bortezomib, celecoxib, denileukin diftitox, estramustine,hydroxycarbamide, irinotecan, lonidamine, masoprocol, miltefosein,mitoguazone, mitotane, oblimersen, pegaspargase, pentostatin,romidepsin, sitimagene ceradenovec, tiazofurine, topotecan, tretinoin,vorinostat, diethylstilbenol, ethinylestradiol, fosfestrol,polyestradiol phosphate, gestonorone, medroxyprogesterone, megestrol,buserelin, goserelin, leuprorelin, triptorelin, fulvestrant, tamoxifen,toremifene, bicalutamide, flutamide, nilutamide, aminoglutethimide,anastrozole, exemestane, formestane, letrozole, vorozole, abarelix,degarelix, histamine dihydrochloride, mifamurtide, pidotimod,plerixafor, roquinimex, thymopentin, everolimus, gusperimus,leflunomide, mycophenolic acid, sirolimus, ciclosporin, tacrolimus,azathioprine, lenalidomide, methotrexate, thalidomide, iobenguane,ancestim, filgrastim, lenograstim, molgramostim, pegfilgrastim,sargramostim, interferon alfa natural, interferon alfa-2a, interferonalfa-2b, interferon alfacon-1, interferon alfa-nl, interferon betanatural, interferon beta-1a, interferon beta-1b, interferon gamma,peginterferon alfa-2a, peginterferon alfa-2b, aldesleukin, oprelvekin,BCG vaccine, glatiramer acetate, histamine dihydrochloride,immunocyanin, lentinan, melanoma vaccine, mifamurtide, pegademase,pidotimod, plerixafor, poly I:C, poly ICLC, roquinimex, tasonermin,thymopentin, abatacept, abetimus, alefacept, antilymphocyteimmunoglobulin (horse), antithymocyte immunoglobulin (rabbit),eculizumab, efalizumab, everolimus, gusperimus, leflunomide,muromab-CD3, mycophenolic acid, natalizumab, sirolimus, adalimumab,afelimomab, certolizumab pegol, etanercept, golimumab, infliximab,anakinra, basiliximab, canakinumab, daclizumab, mepolizumab, rilonacept,tocilizumab, ustekinumab, ciclosporin, tacrolimus, azathioprine,lenalidomide, methotrexate, thalidomide, adalimumab, alemtuzumab,bevacizumab, cetuximab, certolizumab pegol, eculizumab, efalizumab,gemtuzumab, ibritumomab tiuxetan, muromonab-CD3, natalizumab,panitumumab, ranibizumab, rituximab, tositumomab, trastuzumab,catumaxomab, edrecolomab, ofatumumab, muromab-CD3, afelimomab,golimumab, ibritumomab tiuxetan, abagovomab, adecatumumab, alemtuzumab,anti-CD30 monoclonal antibody Xmab2513, anti-MET monoclonal antibodyMetMab, apolizumab, apomab, arcitumomab, bispecific antibody 2B1,blinatumomab, brentuximab vedotin, capromab pendetide, cixutumumab,claudiximab, conatumumab, dacetuzumab, denosumab, eculizumab,epratuzumab, epratuzumab, ertumaxomab, etaracizumab, figitumumab,fresolimumab, galiximab, ganitumab, gemtuzumab ozogamicin,glembatumumab, ibritumomab, inotuzumab ozogamicin, ipilimumab,lexatumumab, lintuzumab, lintuzumab, lucatumumab, mapatumumab,matuzumab, milatuzumab, monoclonal antibody CC49, necitumumab,nimotuzumab, ofatumumab, oregovomab, pertuzumab, ramacurimab,ranibizumab, siplizumab, sonepcizumab, tanezumab, tositumomab,trastuzumab, tremelimumab, tucotuzumab celmoleukin, veltuzumab,visilizumab, volociximab, zalutumumab, a syk inhibitor (e.g., R788),enzastaurin, dasatinib, erlotinib, everolimus, gefitinib, imatinib,lapatinib, nilotinib, pazonanib, sorafenib, sunitinib, temsirolimus, anangiogenesis inhibitor (e.g., GT-111, JI-101, R1530), a kinaseinhibitors (e.g., AC220, AC480, ACE-041, AMG 900, AP24534, Arry-614,AT7519, AT9283, AV-951, axitinib, AZD1152, AZD7762, AZD8055, AZD8931,bafetinib, BAY 73-4506, BGJ398, BGT226, BI 811283, BI6727, BIBF 1120,BIBW 2992, BMS-690154, BMS-777607, BMS-863233, BSK-461364, CAL-101,CEP-11981, CYC116, DCC-2036, dinaciclib, dovitinib lactate, E7050, EMD1214063, ENMD-2076, fostamatinib disodium, GSK2256098, GSK690693,INCB18424, INNO-406, JNJ-26483327, JX-594, KX2-391, linifanib,LY2603618, MGCD265, MK-0457, MK1496, MLN8054, MLN8237, MP470,NMS-1116354, NMS-1286937, ON 01919.Na, OSI-027, OSI-930, Btk inhibitor,PF-00562271, PF-02341066, PF-03814735, PF-04217903, PF-04554878,PF-04691502, PF-3758309, PHA-739358, PLC3397, progenipoietin, R547,R763, ramucirumab, regorafenib, R05185426, SAR103168, S3333333CH 727965,SGI-1176, SGX523, SNS-314, TAK-593, TAK-901, TKI258, TLN-232, TTP607,XL147, XL228, XL281RO5126766, XL418, XL765), an inhibitor ofmitogen-activated protein kinase signaling (e.g., U0126, PD98059,PD184352, PD0325901, ARRY-142886, SB239063, SP600125, BAY 43-9006,wortmannin, or LY294002), adriamycin, dactinomycin, bleomycin,vinblastine, cisplatin, acivicin, aclarubicin, acodazole hydrochloride,acronine, adozelesin, aldesleukin, altretamine, ambomycin, ametantroneacetate, aminoglutethimide, amsacrine, anastrozole, anthramycin,asparaginase, asperlin, azacitidine, azetepa, azotomycin, batimastat,benzodepa, bicalutamide, bisantrene hydrochloride, bisnafide dimesylate,bizelesin, bleomycin sulfate, brequinar sodium, bropirimine, busulfan,cactinomycin, calusterone, caracemide, carbetimer, carboplatin,carmustine, carubicin hydrochloride, carzelesin, cedefingol,chlorambucil, cirolemycin, cladribine, crisnatol mesylate,cyclophosphamide, cytarabine, dacarbazine, daunorubicin hydrochloride,decitabine, dexormaplatin, dezaguanine, dezaguanine mesylate,diaziquone, doxorubicin, doxorubicin hydrochloride, droloxifene,droloxifene citrate, dromostanolone propionate, duazomycin, edatrexate,eflornithine hydrochloride, elsamitrucin, enloplatin, enpromate,epipropidine, epirubicin hydrochloride, erbulozole, esorubicinhydrochloride, estramustine, estramustine phosphate sodium, etanidazole,etoposide, etoposide phosphate, etoprine, fadrozole hydrochloride,fazarabine, fenretinide, floxuridine, fludarabine phosphate,fluorouracil, flurocitabine, fosquidone, fostriecin sodium, gemcitabine,gemcitabine hydrochloride, hydroxyurea, idarubicin hydrochloride,ifosfamide, iimofosine, interleukin Il (including recombinantinterleukin II, or rlL2), interferon alfa-2a, interferon alfa-2b,interferon alfa-nl, interferon alfa-n3, interferon beta-1 a, interferongamma-1 b, iproplatin, irinotecan hydrochloride, lanreotide acetate,letrozole, leuprolide acetate, liarozole hydrochloride, lometrexolsodium, lomustine, losoxantrone hydrochloride, masoprocol, maytansine,mechlorethamine hydrochloride, megestrol acetate, melengestrol acetate,melphalan, menogaril, mercaptopurine, methotrexate, methotrexate sodium,metoprine, meturedepa, mitindomide, mitocarcin, mitocromin, mitogillin,mitomalcin, mitomycin, mitosper, mitotane, mitoxantrone hydrochloride,mycophenolic acid, nocodazoie, nogalamycin, ormaplatin, oxisuran,pegaspargase, peliomycin, pentamustine, peplomycin sulfate,perfosfamide, pipobroman, piposulfan, piroxantrone hydrochloride,plicamycin, plomestane, porfimer sodium, porfiromycin, prednimustine,procarbazine hydrochloride, puromycin, puromycin hydrochloride,pyrazofurin, riboprine, rogletimide, safingol, safingol hydrochloride,semustine, simtrazene, sparfosate sodium, sparsomycin, spirogermaniumhydrochloride, spiromustine, spiroplatin, streptonigrin, streptozocin,sulofenur, talisomycin, tecogalan sodium, tegafur, teloxantronehydrochloride, temoporfin, teniposide, teroxirone, testolactone,thiamiprine, thioguanine, thiotepa, tiazofurin, tirapazamine, toremifenecitrate, trestolone acetate, triciribine phosphate, trimetrexate,trimetrexate glucuronate, triptorelin, tubulozole hydrochloride, uracilmustard, uredepa, vapreotide, verteporfin, vinblastine sulfate,vincristine sulfate, vindesine, vindesine sulfate, vinepidine sulfate,vinglycinate sulfate, vinleurosine sulfate, vinorelbine tartrate,vinrosidine sulfate, vinzolidine sulfate, vorozole, zeniplatin,zinostatin, zorubicin hydrochloride. In some embodiments, thetherapeutic agent is selected from: 20-epi-1, 25 dihydroxyvitamin D3,5-ethynyluracil, abiraterone, aclarubicin, acylfulvene, adecypenol,adozelesin, aldesleukin, ALL-TK antagonists, altretamine, ambamustine,amidox, amifostine, aminolevulinic acid, amrubicin, amsacrine,anagrelide, anastrozole, andrographolide, angiogenesis inhibitors,antagonist D, antagonist G, antarelix, anti-dorsalizing morphogeneticprotein-1, antiandrogen, prostatic carcinoma, antiestrogen,antineoplaston, antisense oligonucleotides, aphidicolin glycinate,apoptosis gene modulators, apoptosis regulators, apurinic acid,ara-CDP-DL-PTBA, arginine deaminase, asulacrine, atamestane,atrimustine, axinastatin 1, axinastatin 2, axinastatin 3, azasetron,azatoxin, azatyrosine, baccatin III derivatives, balanol, batimastat,BCR/ABL antagonists, benzochlorins, benzoylstaurosporine, beta lactamderivatives, beta-alethine, betaclamycin B, betulinic acid, bFGFinhibitor, bicalutamide, bisantrene, bisaziridinylspermine, bisnafide,bistratene A, bizelesin, breflate, bropirimine, budotitane, buthioninesulfoximine, calcipotriol, calphostin C, camptothecin derivatives,canarypox IL-2, capecitabine, carboxamide-amino-triazole,carboxyamidotriazole, CaRest M3, CARN 700, cartilage derived inhibitor,carzelesin, casein kinase inhibitors (ICOS), castanospermine, cecropinB, cetrorelix, chlorins, chloroquinoxaline sulfonamide, cicaprost,cis-porphyrin, cladribine, clomifene analogues, clotrimazole,collismycin A, collismycin B, combretastatin A4, combretastatinanalogue, conagenin, crambescidin 816, crisnatol, cryptophycin 8,cryptophycin A derivatives, curacin A, cyclopentanthraquinones,cycloplatam, cypemycin, cytarabine ocfosfate, cytolytic factor,cytostatin, dacliximab, decitabine, dehydrodidemnin B, deslorelin,dexamethasone, dexifosfamide, dexrazoxane, dexverapamil, diaziquone,didemnin B, didox, diethylnorspermine, dihydro-5-azacytidine,9-dioxamycin, diphenyl spiromustine, docosanol, dolasetron,doxifluridine, droloxifene, dronabinol, duocarmycin SA, ebselen,ecomustine, edelfosine, edrecolomab, eflornithine, elemene, emitefur,epirubicin, epristeride, estramustine analogue, estrogen agonists,estrogen antagonists, etanidazole, etoposide phosphate, exemestane,fadrozole, fazarabine, fenretinide, filgrastim, finasteride,flavopiridol, flezelastine, fluasterone, fludarabine, fluorodaunorunicinhydrochloride, forfenimex, formestane, fostriecin, fotemustine,gadolinium texaphyrin, gallium nitrate, galocitabine, ganirelix,gelatinase inhibitors, gemcitabine, glutathione inhibitors, hepsulfam,heregulin, hexamethylene bisacetamide, hypericin, ibandronic acid,idarubicin, idoxifene, idramantone, ilmofosine, ilomastat,imidazoacridones, imiquimod, immunostimulant peptides, insulin-such asfor example growth factor-1 receptor inhibitor, interferon agonists,interferons, interleukins, iobenguane, iododoxorubicin, ipomeanol, 4-,iroplact, irsogladine, isobengazole, isohomohalicondrin B, itasetron,jasplakinolide, kahalalide F, lamellarin-N triacetate, lanreotide,leinamycin, lenograstim, lentinan sulfate, leptolstatin, letrozole,leukemia inhibiting factor, leukocyte alpha interferon,leuprolide+estrogen+progesterone, leuprorelin, levamisole, liarozole,linear polyamine analogue, lipophilic disaccharide peptide, lipophilicplatinum compounds, lissoclinamide 7, lobaplatin, lombricine,lometrexol, lonidamine, losoxantrone, lovastatin, loxoribine,lurtotecan, lutetium texaphyrin, lysofylline, lytic peptides,maitansine, mannostatin A, marimastat, masoprocol, maspin, matrilysininhibitors, matrix metalloproteinase inhibitors, menogaril, merbarone,meterelin, methioninase, metoclopramide, MIF inhibitor, mifepristone,miltefosine, mirimostim, mismatched double stranded RNA, mitoguazone,mitolactol, mitomycin analogues, mitonafide, mitotoxin fibroblast growthfactor-saporin, mitoxantrone, mofarotene, molgramostim, monoclonalantibody, human chorionic gonadotrophin, monophosphoryl lipidA+myobacterium cell wall sk, mopidamol, multiple drug resistance geneinhibitor, multiple tumor suppressor 1-based therapy, mustard anticanceragent, mycaperoxide B, mycobacterial cell wall extract, myriaporone,N-acetyldinaline, N-substituted benzamides, nafarelin, nagrestip,naloxone+pentazocine, napavin, naphterpin, nartograstim, nedaplatin,nemorubicin, neridronic acid, neutral endopeptidase, nilutamide,nisamycin, nitric oxide modulators, nitroxide antioxidant, nitrullyn,O6-benzylguanine, octreotide, okicenone, oligonucleotides, onapristone,ondansetron, ondansetron, oracin, oral cytokine inducer, ormaplatin,osaterone, oxaliplatin, oxaunomycin, palauamine, palmitoylrhizoxin,pamidronic acid, panaxytriol, panomifene, parabactin, pazelliptine,pegaspargase, peldesine, pentosan polysulfate sodium, pentostatin,pentrozole, perflubron, perfosfamide, perillyl alcohol, phenazinomycin,phenylacetate, phosphatase inhibitors, picibanil, pilocarpinehydrochloride, pirarubicin, piritrexim, placetin A, placetin B,plasminogen activator inhibitor, platinum complex, platinum compounds,platinum-triamine complex, porfimer sodium, porfiromycin, prednisone,propyl bis-acridone, prostaglandin J2, proteasome inhibitors, proteinA-based immune modulator, protein kinase C inhibitor, protein kinase Cinhibitors, microalgal, protein tyrosine phosphatase inhibitors, purinenucleoside phosphorylase inhibitors, purpurins, pyrazoloacridine,pyridoxylated hemoglobin polyoxyethylerie conjugate, raf antagonists,raltitrexed, ramosetron, ras farnesyl protein transferase inhibitors,ras inhibitors, ras-GAP inhibitor, retelliptine demethylated, rhenium Re186 etidronate, rhizoxin, ribozymes, RII retinamide, rogletimide,rohitukine, romurtide, roquinimex, rubiginone B1, ruboxyl, safingol,saintopin, SarCNU, sarcophytol A, sargramostim, Sdi 1 mimetics,semustine, senescence derived inhibitor 1, sense oligonucleotides,signal transduction inhibitors, signal transduction modulators, singlechain antigen-binding protein, sizofiran, sobuzoxane, sodiumborocaptate, sodium phenylacetate, solverol, somatomedin bindingprotein, sonermin, sparfosic acid, spicamycin D, spiromustine,splenopentin, spongistatin 1, squalamine, stem cell inhibitor, stem-celldivision inhibitors, stipiamide, stromelysin inhibitors, sulfinosine,superactive vasoactive intestinal peptide antagonist, suradista,suramin, swainsonine, synthetic glycosaminoglycans, tallimustine,tamoxifen methiodide, tauromustine, tazarotene, tecogalan sodium,tegafur, tellurapyrylium, telomerase inhibitors, temoporfin,temozolomide, teniposide, tetrachlorodecaoxide, tetrazomine,thaliblastine, thiocoraline, thrombopoietin, thrombopoietin mimetic,thymalfasin, thymopoietin receptor agonist, thymotrinan, thyroidstimulating hormone, tin ethyl etiopurpurin, tirapazamine, titanocenebichloride, topsentin, toremifene, totipotent stem cell factor,translation inhibitors, tretinoin, triacetyluridine, triciribine,trimetrexate, triptorelin, tropisetron, turosteride, tyrosine kinaseinhibitors, tyrphostins, UBC inhibitors, ubenimex, urogenitalsinus-derived growth inhibitory factor, urokinase receptor antagonists,vapreotide, variolin B, vector system, erythrocyte gene therapy,velaresol, veramine, verdins, verteporfin, vinorelbine, vinxaltine,vitaxin, vorozole, zanoterone, zeniplatin, zilascorb, zinostatinstimalamer, mechloroethamine, cyclophosphamide, chlorambucil, busulfan,carmustine, lomusitne, decarbazine, methotrexate, cytarabine,mercaptopurine, thioguanine, pentostatin, mechloroethamine,cyclophosphamide, chlorambucil, meiphalan, ethylenimine, methylmelamine,hexamethlymelamine, thiotepa, busulfan, carmustine, lomusitne,semustine, streptozocin, decarbazine, fluorouracil, floxouridine,cytarabine, mercaptopurine, thioguanine, pentostatin, erbulozole (alsoknown as R-55104), Dolastatin 10 (also known as DLS-10 and NSC-376128),Mivobulin isethionate (also known as CI-980), Vincristine, NSC-639829,Discodermolide (also known as NVP-XX-A-296), ABT-751 (Abbott, also knownas E-7010), Altorhyrtins (such as Altorhyrtin A and Altorhyrtin C),Spongistatins (such as Spongistatin 1, Spongistatin 2, Spongistatin 3,Spongistatin 4, Spongistatin 5, Spongistatin 6, Spongistatin 7,Spongistatin 8, and Spongistatin 9), Cemadotin hydrochloride (also knownas LU-103793 and NSC-D-669356), Epothilones (such as Epothilone A,Epothilone B, Epothilone C (also known as desoxyepothilone A or dEpoA),Epothilone D (also referred to as KOS-862, dEpoB, and desoxyepothiloneB), Epothilone E, Epothilone F, Epothilone B N-oxide, Epothilone AN-oxide, 16-aza-epothilone B, 21-aminoepothilone B (also known asBMS-310705), 21-hydroxyepothilone D (also known as Desoxyepothilone Fand dEpoF), 26-fluoroepothilone), Auristatin PE (also known asNSC-654663), Soblidotin (also known as TZT-1027), LS-4559-P (Pharmacia,also known as LS-4577), LS-4578 (Pharmacia, also known as LS-477-P),LS-4477 (Pharmacia), LS-4559 (Pharmacia), RPR-112378 (Aventis),Vincristine sulfate, DZ-3358 (Daiichi), FR-182877 (Fujisawa, also knownas WS-9885B), GS-164 (Takeda), GS-198 (Takeda), KAR-2 (Hungarian Academyof Sciences), BSF-223651 (BASF, also known as ILX-651 and LU-223651),SAH-49960 (Lilly/Novartis), SDZ-268970 (Lilly/Novartis), AM-97(Armad/Kyowa Hakko), AM-132 (Armad), AM-138 (Armad/Kyowa Hakko),IDN-5005 (Indena), Cryptophycin 52 (also known as LY-355703), AC-7739(Ajinomoto, also known as AVE-8063A and CS-39.HCI), AC-7700 (Ajinomoto,also known as AVE-8062, AVE-8062A, CS-39-L-Ser.HCI, and RPR-258062A),Vitilevuamide, Tubulysin A, Canadensol, Centaureidin (also known asNSC-106969), T-138067 (Tularik, also known as T-67, TL-138067 andTI-138067), COBRA-1 (Parker Hughes Institute, also known as DDE-261 andWHI-261), H10 (Kansas State University), H16 (Kansas State University),Oncocidin A1 (also known as BTO-956 and DIME), DDE-313 (Parker HughesInstitute), Fijianolide B, Laulimalide, SPA-2 (Parker Hughes Institute),SPA-1 (Parker Hughes Institute, also known as SPIKET-P), 3-IAABU(Cytoskeleton/Mt. Sinai School of Medicine, also known as MF-569),Narcosine (also known as NSC-5366), Nascapine, D-24851 (Asta Medica),A-105972 (Abbott), Hemiasterlin, 3-BAABU (Cytoskeleton/Mt. Sinai Schoolof Medicine, also known as MF-191), TMPN (Arizona State University),Vanadocene acetylacetonate, T-138026 (Tularik), Monsatrol, lnanocine(also known as NSC-698666), 3-1AABE (Cytoskeleton/Mt. Sinai School ofMedicine), A-204197 (Abbott), T-607 (Tuiarik, also known as T-900607),RPR-115781 (Aventis), Eleutherobins (such as Desmethyleleutherobin,Desaetyleleutherobin, lsoeleutherobin A, and Z-Eleutherobin),Caribaeoside, Caribaeolin, Halichondrin B, D-64131 (Asta Medica),D-68144 (Asta Medica), Diazonamide A, A-293620 (Abbott), NPI-2350(Nereus), Taccalonolide A, TUB-245 (Aventis), A-259754 (Abbott),Diozostatin, (−)-Phenylahistin (also known as NSCL-96F037), D-68838(Asta Medica), D-68836 (Asta Medica), Myoseverin B, D-43411 (Zentaris,also known as D-81862), A-289099 (Abbott), A-318315 (Abbott), HTI-286(also known as SPA-110, trifluoroacetate salt) (Wyeth), D-82317(Zentaris), D-82318 (Zentaris), SC-12983 (NCI), Resverastatin phosphatesodium, BPR-OY-007 (National Health Research Institutes), and SSR-250411(Sanofi).

In some embodiments, the therapeutic agent is an anti-inflammatoryagent. In some embodiments, the therapeutic agent is an anti-TNF agent,an IL-1 receptor antagonist, an IL-2 receptor antagonist, a cytotoxicagent, an immunomodulatory agent, an antibiotic, a T-cell co-stimulatoryblocker, a B cell depleting agent, an immunosuppressive agent, analkylating agent, an anti-metabolite, a plant alkaloid, a terpenoids, atopoisomerase inhibitor, an antitumour antibiotic, an antibody, ahormonal therapy, an anti-diabetes agent, a leukotriene inhibitor, orcombinations thereof. In some embodiments, the therapeutic agent isselected from: alefacept, efalizumab, methotrexate, acitretin,isotretinoin, hydroxyurea, mycophenolate mofetil, sulfasalazine,6-Thioguanine, Dovonex, Taclonex, betamethasone, tazarotene,hydroxychloroquine, etanercept, adalimumab, infliximab, abatacept,rituximab, tratuzumab, Anti-CD45 monoclonal antibody AHN-12 (NCI),Iodine-131 Anti-B1 Antibody (Corixa Corp.), anti-CD66 monoclonalantibody BW 250/183 (NCI, Southampton General Hospital), anti-CD45monoclonal antibody (NCI, Baylor College of Medicine), antibodyanti-anb3 integrin (NCI), BIW-8962 (BioWa Inc.), Antibody BC8 (NCI),antibody muJ591 (NCI), indium In 111 monoclonal antibody MN-14 (NCI),yttrium Y 90 monoclonal antibody MN-14 (NCI), F105 Monoclonal Antibody(NIAID), Monoclonal Antibody RAV12 (Raven Biotechnologies), CAT-192(Human Anti-TGF-Beta1 Monoclonal Antibody, Genzyme), antibody 3F8 (NCI),177Lu-J591 (Weill Medical College of Cornell University), TB-403(Biolnvent International AB), anakinra, azathioprine, cyclophosphamide,cyclosporine A, leflunomide, d-penicillamine, amitriptyline, ornortriptyline, chlorambucil, nitrogen mustard, prasterone, LJP 394(abetimus sodium), LJP 1082 (La Jolla Pharmaceutical), eculizumab,belibumab, rhuCD40L (NIAID), epratuzumab, sirolimus, tacrolimus,pimecrolimus, thalidomide, antithymocyte globulin-equine (Atgam,Pharmacia Upjohn), antithymocyte globulin-rabbit (Thymoglobulin,Genzyme), Muromonab-CD3 (FDA Office of Orphan Products Development),basiliximab, daclizumab, riluzole, cladribine, natalizumab, interferonbeta-1b, interferon beta-1a, tizanidine, baclofen, mesalazine, asacol,pentasa, mesalamine, balsalazide, olsalazine, 6-mercaptopurine, AIN457(Anti IL-17 Monoclonal Antibody, Novartis), theophylline, D2E7 (a humananti-TNF mAb from Knoll Pharmaceuticals), Mepolizumab (Anti-IL-5antibody, SB 240563), Canakinumab (Anti-IL-1 Beta Antibody, NIAMS),Anti-IL-2 Receptor Antibody (Daclizumab, NHLBI), CNTO 328 (Anti IL-6Monoclonal Antibody, Centocor), ACZ885 (fully humananti-interleukin-1beta monoclonal antibody, Novartis), CNTO 1275 (FullyHuman Anti-IL-12 Monoclonal Antibody, Centocor),(3S)—N-hydroxy-4-({4-[(4-hydroxy-2-butynyl)oxy]phenyl}sulfonyl)-2,2-dimet-hyl-3-thiomorpholinecarboxamide (apratastat), golimumab (CNTO 148), Onercept, BG9924 (BiogenIdec), Certolizumab Pegol (CDP870, UCB Pharma), AZD9056 (AstraZeneca),AZD5069 (AstraZeneca), AZD9668 (AstraZeneca), AZD7928 (AstraZeneca),AZD2914 (AstraZeneca), AZD6067 (AstraZeneca), AZD3342 (AstraZeneca),AZD8309 (AstraZeneca),[(1R)-3-methyl-1-({(2S)-3-phenyl-2-[(pyrazin-2-ylcarbonyl)amino]propanoyl}amino)butyl]boronicacid (Bortezomib), AMG-714, (Anti-IL 15 Human Monoclonal Antibody,Amgen), ABT-874 (Anti IL-12 monoclonal antibody, Abbott Labs), MRA(Tocilizumab, an Anti IL-6 Receptor Monoclonal Antibody, ChugaiPharmaceutical), CAT-354 (a human anti-interleukin-13 monoclonalantibody, Cambridge Antibody Technology, MedImmune), aspirin, salicylicacid, gentisic acid, choline magnesium salicylate, choline salicylate,choline magnesium salicylate, choline salicylate, magnesium salicylate,sodium salicylate, diflunisal, carprofen, fenoprofen, fenoprofencalcium, flurobiprofen, ibuprofen, ketoprofen, nabutone, ketolorac,ketorolac tromethamine, naproxen, oxaprozin, diclofenac, etodolac,indomethacin, sulindac, tolmetin, meclofenamate, meclofenamate sodium,mefenamic acid, piroxicam, meloxicam, celecoxib, rofecoxib, valdecoxib,parecoxib, etoricoxib, lumiracoxib, CS-502 (Sankyo), JTE-522 (JapanTobacco Inc.), L-745,337 (Almirall), NS398 (Sigma), betamethasone(Celestone), prednisone (Deltasone), alclometasone, aldosterone,amcinonide, beclometasone, betamethasone, budesonide, ciclesonide,clobetasol, clobetasone, clocortolone, cloprednol, cortisone,cortivazol, deflazacort, deoxycorticosterone, desonide, desoximetasone,desoxycortone, dexamethasone, diflorasone, diflucortolone,difluprednate, fluclorolone, fludrocortisone, fludroxycortide,flumetasone, flunisolide, fluocinolone acetonide, fluocinonide,fluocortin, fluocortolone, fluorometholone, fluperolone, fluprednidene,fluticasone, formocortal, formoterol, halcinonide, halometasone,hydrocortisone, hydrocortisone aceponate, hydrocortisone buteprate,hydrocortisone butyrate, loteprednol, medrysone, meprednisone,methylprednisolone, methylprednisolone aceponate, mometasone furoate,paramethasone, prednicarbate, prednisone, rimexolone, tixocortol,triamcinolone, ulobetasol, Pioglitazone, Rosiglitazone, Glimepiride,Glyburide, Chlorpropamide, Glipizide, Tolbutamide, Tolazamide,Glucophage, Metformin, (glyburide+metformin), Rosiglitazone+metformin,(Rosiglitazone+glimepiride), Exenatide, Insulin, Sitagliptin, (glipizideand metformin), Repaglinide, Acarbose, Nateglinide, Orlistat, cisplatin;carboplatin; oxaliplatin; mechlorethamine; cyclophosphamide;chlorambucil; vincristine; vinblastine; vinorelbine; vindesine;mercaptopurine; fludarabine; pentostatin; cladribine; 5-fluorouracil(5FU); floxuridine (FUDR); cytosine arabinoside; trimethoprim;pyrimethamine; pemetrexed; paclitaxel; docetaxel; etoposide; teniposide;irinotecan; topotecan; amsacrine; etoposide; etoposide phosphate;teniposide; dactinomycin; doxorubicin; daunorubicin; valrubicine;idarubicine; epirubicin; bleomycin; plicamycin; mitomycin; finasteride;goserelin; aminoglutethimide; anastrozole; letrozole; vorozole;exemestane; 4-androstene-3,6,17-trione (“6-OXO”;1,4,6-androstatrien-3,17-dione (ATD); formestane; testolactone;fadrozole; A-81834(3-(3-(1,1-dimethylethylthio-5-(quinoline-2-ylmethoxy)-1-(4-chloromethylphenyl)indole-2-yl)-2,2-dimethylpropionaldehydeoxime-O-2-acetic acid; AME103 (Amira); AME803 (Amira); atreleuton;BAY-x-1005((R)-(+)-alpha-cyclopentyl-4-(2-quinolinylmethoxy)-Benzeneacetic acid);CJ-13610(4-(3-(4-(2-Methyl-imidazol-1-yl)-phenylsulfanyl)-phenyl)-tetrahydro-pyran-4-carboxylicacid amide); DG-031 (DeCode); DG-051 (DeCode); MK886(1-[(4-chlorophenyl)methyl]3-[(1,1-dimethylethyl)thio]-α,α-dimethyl-5-(1-methylethyl)-1H-indole-2-propanoicacid, sodium salt); MK591(3-(1-4[(4-chlorophenyl)methyl]-3-[(t-butylthio)-5-((2-quinoly)methoxy)-1H-indole-2]-,dimehtylpropanoic acid); RP64966([4-[5-(3-Phenyl-propyl)thiophen-2-yl]butoxy] acetic acid); SA6541((R)—S-[[4-(dimethylamino)phenyl]methyl]-N-(3-mercapto-2methyl-1-oxopropyl-L-cycteine);SC-56938 (ethyl-1-[2-[4-(phenylmethyl)phenoxy]ethyl]-4-piperidine-carboxylate); VIA-2291 (Via Pharmaceuticals);WY-47,288 (2-[(1-naphthalenyloxy)methyl]quinoline); zileuton; ZD-2138(6-((3-fluoro-5-(tetrahydro-4-methoxy-2H-pyran-4yl)phenoxy)methyl)-1-methyl-2(1H)-quinlolinone);doxycycline; or combinations thereof.

Macromolecular Carriers

The term “carrier” means an inert molecule that modulates plasmahalf-life, solubility, or bio-distribution. In some embodiments, acarrier modulates plasma half-life of a selective delivery moleculedisclosed herein. In some embodiments, a carrier modulates solubility ofa selective delivery molecule disclosed herein. In some embodiments, acarrier modulates bio-distribution of a selective delivery moleculedisclosed herein.

In some embodiments, a carrier decreases uptake of a selective deliverymolecule by non-target cells or tissues. In some embodiments, a carrierdecreases uptake of a selective delivery molecule into cartilage. Insome embodiments, a carrier decreases uptake of a selective deliverymolecule into joints relative to target tissue.

In some embodiments, a carrier increases uptake of a selective deliverymolecule by target cells or tissues. In some embodiments, a carrierdecreases uptake of a selective delivery molecule into the liverrelative to target tissue. In some embodiments, a carrier decreasesuptake of a selective delivery molecule into kidneys. In someembodiments, a carrier enhances uptake into cancer tissue. In someembodiments, a carrier enhances uptake into lymphatic channels and/orlymph nodes.

In some embodiments, a carrier increases plasma half-life by reducingglomerular filtration. In some embodiments, a carrier modulates plasmahalf-life by increasing or decreases metabolism or protease degradation.In some embodiments, a carrier increases tumor uptake due to enhancedpermeability and retention (EPR) of tumor vasculature. In someembodiments, a carrier increases the aqueous solubility of selectivedelivery molecule.

In some embodiments, any M is independently directly or indirectly(e.g., via c_(M)) bound to A, B, or X. In some embodiments, any M isindependently bound to A at the n-terminal poly glutamate. In someembodiments, any M is independently bound to A (or, the n-terminal polyglutamate) by a covalent linkage. In some embodiments, any M isindependently bound to B at the c-terminal polyarginine. In someembodiments, any M is independently bound to B (or, the c-terminalpolyarginine) by a covalent linkage. In some embodiments, any M isindependently directly or indirectly bound to linkers between X and A, Xand B, B and C/N terminus, and A and C/N terminus. In some embodiments,the covalent linkage comprises an ether bond, thioether bond, aminebond, amide bond, oxime bond, carbon-carbon bond, carbon-nitrogen bond,carbon-oxygen bond, or carbon-sulfur bond.

In some embodiments, M is selected from a protein, a synthetic ornatural polymer, or a dendrimer. In some embodiments, M is selected fromdextran, a PEG polymer (e.g., PEG 5 kDa, PEG 12 kDa, PEG 20 kDa, PEG 30kDa, and PEG40 kDa), albumin, or a combination thereof. In someembodiments, M is a PEG polymer.

In some embodiments, the size of M is between 50 and 70 kD.

In some embodiments, the selective delivery molecule is conjugated toalbumin. In certain instances, albumin is excluded from the glomerularfiltrate under normal physiological conditions. In some embodiments, theselective delivery molecule comprises a reactive group such as maleimidethat can form a covalent conjugate with albumin. A selective deliverymolecule comprising albumin results in enhanced accumulation of cleavedselective delivery molecules in tumors in a cleavage dependent manner.In some embodiments, albumin conjugates have good pharmacokineticproperties.

In some embodiments, the selective delivery molecule is conjugated to aPEG polymer. In some embodiments, the selective delivery molecule isconjugated to a PEG 5 kDa polymer. In some embodiments, the selectivedelivery molecule is conjugated to a PEG 12 kDa polymer. In someembodiments, selective delivery molecule is conjugated to a PEG 20 kDapolymer. In some embodiments, 30 kD PEG conjugates had a longerhalf-life as compared to free peptides. In some embodiments, selectivedelivery molecules are conjugated to 20-40 kD PEG polymer which hashepatic and renal clearance.

In some embodiments, the selective delivery molecule is conjugated to adextran. In some embodiments, the selective delivery molecule isconjugated to a 70 kDa dextran. In some embodiments, dextran conjugates,being a mixture of molecular weights, are difficult to synthesize andpurify reproducibly.

In some embodiments, the selective delivery molecule is conjugated tostreptavidin.

In some embodiments, the selective delivery molecule is conjugated to afifth generation PAMAM dendrimer.

In some embodiments, a carrier is capped. In some embodiments, capping acarrier improves the pharmacokinetics and reduces cytotoxicity of acarrier by adding hydrophilicity. In some embodiments, the cap isselected from: Acetyl, succinyl, 3-hydroxypropionyl, 2-sulfobenzoyl,glycidyl, PEG-2, PEG-4, PEG-8 and PEG-12.

Portion X (Linkers)

In some embodiments, a linker consisting of one or more amino acids isused to join peptide sequence A (i.e., the sequence designed to inhibitthe delivery action of peptide B) and peptide sequence B. Generally thepeptide linker will have no specific biological activity other than tojoin the molecules or to preserve some minimum distance or other spatialrelationship between them. However, the constituent amino acids of thelinker may be selected to influence some property of the molecule suchas the folding, net charge, or hydrophobicity.

In live cells, an intact selective delivery molecule disclosed hereinmay not be able to enter the cell because of the presence of portion A.Thus, a strictly intracellular process for cleaving X would beineffective to cleave X in healthy cells since portion A, preventinguptake into cells, would not be effectively cleaved by intracellularenzymes in healthy cells since it would not be taken up and would notgain access to such intracellular enzymes. However, where a cell isinjured or diseased (e.g., cancerous cells, hypoxic cells, ischemiccells, apoptotic cells, necrotic cells) such intracellular enzymes leakout of the cell and cleavage of A would occur, allowing entry of portionB and/or cargo into the cell, effecting targeted delivery of portion Band/or cargo D to neighboring cells. In some embodiments, X is cleavedin the extracellular space.

In some embodiments, the fact that capillaries are often leaky aroundtumors and other trauma sites enhances the ability of high molecularweight molecules (e.g., molecular weight of about 30 kDa or more) toreach the interstitial compartment. In some embodiments, X linkercellsthat do not express the relevant protease but that are immediatelyadjacent to expressing cells pick up cargo from a selective deliverymolecule because linkage of a X linker is typically extracellular. Insome embodiments, such bystander targeting is beneficial in thetreatment of tumors because of the heterogeneity of cell phenotypes andthe wish to eliminate as high a percentage of suspicious cells aspossible.

In some embodiments, X is a cleavable linker.

In some embodiments, the linker is flexible. In some embodiments, thelinker is rigid.

In some embodiments, the linker comprises a linear structure. In someembodiments, the linker comprises a non-linear structure. In someembodiments, the linker comprises a branched structure. In someembodiments, the linker comprises a cyclic structure.

In some embodiments, X is about 5 to about 30 atoms in length. In someembodiments, X is about 6 atoms in length. In some embodiments, X isabout 8 atoms in length. In some embodiments, X is about 10 atoms inlength. In some embodiments, X is about 12 atoms in length. In someembodiments, X is about 14 atoms in length. In some embodiments, X isabout 16 atoms in length. In some embodiments, X is about 18 atoms inlength. In some embodiments, X is about 20 atoms in length. In someembodiments, X is about 25 atoms in length. In some embodiments, X isabout 30 atoms in length.

In some embodiments, the linker binds peptide portion A (i.e., thepeptide sequence which prevents cellular uptake) to peptide portion B(i.e., the delivery sequence) by a covalent linkage. In someembodiments, the covalent linkage comprises an ether bond, thioetherbond, amine bond, amide bond, oxime bond, hydrazone bond, carbon-carbonbond, carbon-nitrogen bond, carbon-oxygen bond, or carbon-sulfur bond.

In some embodiments, X comprises a peptide linkage. The peptide linkagecomprises L-amino acids and/or D-amino acids. In embodiments of theinvention, D-amino acids are preferred in order to minimizeimmunogenicity and nonspecific cleavage by background peptidases orproteases. Cellular uptake of oligo-D-arginine sequences is known to beas good as or better than that of oligo-L-arginines.

In some embodiments, a X linker is designed for cleavage in the presenceof particular conditions or in a particular environment. In preferredembodiments, a X linker is cleavable under physiological conditions.Cleavage of such a X linker may, for example, be enhanced or may beaffected by particular pathological signals or a particular environmentrelated to cells in which cargo delivery is desired. The design of a Xlinker for cleavage by specific conditions, such as by a specificenzyme, allows the targeting of cellular uptake to a specific locationwhere such conditions obtain. Thus, one important way that selectivedelivery molecules provide specific targeting of cellular uptake todesired cells, tissues, or regions is by the design of the linkerportion X to be cleaved by conditions near such targeted cells, tissues,or regions.

In some embodiments, X is a pH-sensitive linker. In some embodiments, Xis cleaved under basic pH conditions. In some embodiments, X is cleavedunder acidic pH conditions. In some embodiments, X is cleaved by aprotease, a matrix metalloproteinase, or a combination thereof. In someembodiments, X is cleaved by a reducing agent.

In some embodiments, X is cleaved by an MMP. The hydrolytic activity ofmatrix metalloproteinases (MMPs) has been implicated in the invasivemigration of metastatic tumor cells. In certain instances, MMPs arefound near sites of inflammation. In certain instances, MMPs are foundnear sites of stroke (i.e., a disorder characterized by brain damagefollowing a decrease in blood flow). Thus, uptake of molecules havingfeatures of the invention are able to direct cellular uptake of cargo(at least one D moiety) to specific cells, tissues, or regions havingactive MMPs in the extracellular environment. In some embodiments, a Xlinker that includes the amino-acid sequences PLG-C(Me)-AG (SEQ ID NO:1), PLGLAG (SEQ ID NO: 2) which are cleaved by the metalloproteinaseenzymes MMP-2, MMP-9, or MMP-7 (MMPs involved in cancer andinflammation).

In some embodiments, X is cleaved by proteolytic enzymes or reducingenvironment, as may be found near cancerous cells. Such an environment,or such enzymes, are typically not found near normal cells.

In some embodiments, X is cleaved by serine proteases including but notlimited to thrombin.

In some embodiments, X is cleaved in or near tissues suffering fromhypoxia. In some embodiments, cleavage in or near hypoxic tissuesenables targeting of cancer cells and cancerous tissues, infarctregions, and other hypoxic regions. In some embodiments, X comprises adisulfide bond. In some embodiments, a linker comprising a disulfidebond is preferentially cleaved in hypoxic regions and so targets cargodelivery to cells in such a region. Hypoxia is thought to cause cancercells to become more resistant to radiation and chemotherapy, and alsoto initiate angiogenesis. In a hypoxic environment in the presence of,for example, leaky or necrotic cells, free thiols and other reducingagents become available extracellularly, while the O₂ that normallykeeps the extracellular environment oxidizing is by definition depleted.In some embodiments, this shift in the redox balance promotes reductionand cleavage of a disulfide bond within a X linker. In addition todisulfide linkages which take advantage of thiol-disulfide equilibria,linkages including quinones that fall apart when reduced tohydroquinones are used in a X linker designed to be cleaved in a hypoxicenvironment.

In some embodiments, X is cleaved in a necrotic environment. Necrosisoften leads to the release of enzymes or other cell contents that may beused to trigger cleavage of a X linker. In some embodiments, cleavage ofX by necrotic enzymes (e.g., by calpains) allows cargo to be taken up bydiseased cells and by neighboring cells that had not yet become fullyleaky.

In some embodiments, X is an acid-labile linker. In some embodiments, Xcomprises an acetal or vinyl ether linkage. Acidosis is observed insites of damaged or hypoxic tissue, due to the Warburg shift fromoxidative phosphorylation to anaerobic glycolysis and lactic acidproduction. In some embodiments, acidosis is used as a trigger of cargouptake by replacing some of the arginines within B by histidines, whichonly become cationic below pH 7.

It will be understood that a linker disclosed herein may includenon-standard amino acids, such as, for example, hydroxylysine,desmosine, isodesmosine, or other non-standard amino acids. A linkerdisclosed herein may include modified amino acids, includingpost-translationally modified amino acids such as, for example,methylated amino acids (e.g., methyl histidine, methylated forms oflysine, etc.), acetylated amino acids, amidated amino acids, formylatedamino acids, hydroxylated amino acids, phosphorylated amino acids, orother modified amino acids. A linker disclosed herein may also includepeptide mimetic moieties, including portions linked by non-peptide bondsand amino acids linked by or to non-amino acid portions.

In some embodiments, the linker X comprises an amino acid sequenceselected from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID NO: 9),PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and RLQLK(Ac) (SEQ IDNO: 12). In some embodiments, the linker X comprises the amino acidsequence PLGLAG (SEQ ID NO: 2). In some embodiments, the linker Xcomprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1). In someembodiments, the linker X comprises the amino acid sequence PLGxAG (SEQID NO: 27), wherein x is any amino acid (naturally-occuring ornon-naturally occurring). In some embodiments, the linker X comprisesthe amino acid sequence RPLALWRS (SEQ ID NO: 7). In some embodiments,the linker X comprises the amino acid sequence ESPAYYTA (SEQ ID NO: 8).In some embodiments, the linker X comprises the amino acid sequenceDPRSFL (SEQ ID NO: 9). In some embodiments, the linker X comprises theamino acid sequence PPRSFL (SEQ ID NO: 10). In some embodiments, thelinker X comprises the amino acid sequence RLQLKL (SEQ ID NO: 11). Insome embodiments, the linker X comprises the amino acid sequenceRLQLK(Ac) (SEQ ID NO: 12).

In some embodiments, the linker X comprises a peptide selected from:PR(S/T)(L/I)(S/T), where the letters in parentheses indicate that eitherone of the indicated amino acids may be at that position in thesequence); GGAANLVRGG (SEQ ID NO: 28); SGRIGFLRTA (SEQ ID NO: 29); SGRSA(SEQ ID NO: 30); GFLG (SEQ ID NO: 31); ALAL (SEQ ID NO: 32); FK;PIC(Et)F-F (SEQ ID NO: 33), where C(Et) indicates S-ethylcysteine (acysteine with an ethyl group attached to the thiol) and the “-”indicates the typical cleavage site in this and subsequent sequences);GGPRGLPG (SEQ ID NO: 34); HSSKLQ (SEQ ID NO: 35); LVLA-SSSFGY (SEQ IDNO: 36); GVSQNY-PIVG (SEQ ID NO: 37); GVVQA-SCRLA (SEQ ID NO: 38);f(Pip)R-S, where “f” indicates D-phenylalanine and “Pip” indicatespiperidine-2-carboxylic acid (pipecolinic acid, a proline analog havinga six-membered ring); DEVD (SEQ ID NO: 39); GWEHDG (SEQ ID NO: 40);RPLALWRS (SEQ ID NO: 7), or a combination thereof.

In some embodiments, X is cleaved under hypoxic conditions. In someembodiments, X comprises a disulfide linkage. In some embodiments, Xcomprises a quinine.

In some embodiments, X is cleaved under necrotic conditions. In someembodiments, X comprises a molecule cleavable by a calpain.

In some embodiments, X comprises 6-aminohexanoyl,5-(amino)-3-oxapentanoyl, or a combination thereof. In some embodiments,X comprises a disulfide linkage.

In some embodiments, the linker is an alkyl. In some embodiments, thelinker is heteroalkyl.

In some embodiments, the linker is an alkylene. In some embodiments, thelinker is an alkenylene. In some embodiments, the linker is analkynylene. In some embodiments, the linker is a heteroalkylene.

An “alkyl” group refers to an aliphatic hydrocarbon group. The alkylmoiety may be a saturated alkyl or an unsaturated alkyl. Depending onthe structure, an alkyl group can be a monoradical or a diradical (i.e.,an alkylene group).

The “alkyl” moiety may have 1 to 10 carbon atoms (whenever it appearsherein, a numerical range such as “1 to 10” refers to each integer inthe given range; e.g., “1 to 10 carbon atoms” means that the alkyl groupmay consist of 1 carbon atom, 2 carbon atoms, 3 carbon atoms, etc., upto and including 10 carbon atoms, although the present definition alsocovers the occurrence of the term “alkyl” where no numerical range isdesignated). The alkyl group could also be a “lower alkyl” having 1 to 6carbon atoms. The alkyl group of the compounds described herein may bedesignated as “C1-C4 alkyl” or similar designations. By way of exampleonly, “C1-C4 alkyl” indicates that there are one to four carbon atoms inthe alkyl chain, i.e., the alkyl chain is selected from: methyl, ethyl,propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, and t-butyl. Typicalalkyl groups include, but are in no way limited to, methyl, ethyl,propyl, isopropyl, butyl, isobutyl, tertiary butyl, pentyl, hexyl,ethenyl, propenyl, butenyl, and the like.

In some embodiments, the linker comprises a ring structure (e.g., anaryl). As used herein, the term “ring” refers to any covalently closedstructure. Rings include, for example, carbocycles (e.g., aryls andcycloalkyls), heterocycles (e.g., heteroaryls and non-aromaticheterocycles), aromatics (e.g. aryls and heteroaryls), and non-aromatics(e.g., cycloalkyls and non-aromatic heterocycles). Rings can beoptionally substituted. Rings can be monocyclic or polycyclic.

As used herein, the term “aryl” refers to an aromatic ring wherein eachof the atoms forming the ring is a carbon atom. Aryl rings can be formedby five, six, seven, eight, nine, or more than nine carbon atoms. Arylgroups can be optionally substituted. Examples of aryl groups include,but are not limited to phenyl, naphthalenyl, phenanthrenyl, anthracenyl,fluorenyl, and indenyl. Depending on the structure, an aryl group can bea monoradical or a diradical (i.e., an arylene group).

The term “cycloalkyl” refers to a monocyclic or polycyclic non-aromaticradical, wherein each of the atoms forming the ring (i.e. skeletalatoms) is a carbon atom. Cycloalkyls may be saturated, or partiallyunsaturated. Cycloalkyl groups include groups having from 3 to 10 ringatoms. Cycloalkyls include, but are not limited to, cyclopropyl,cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl.

In some embodiments, the ring is a cycloalkane. In some embodiments, thering is a cycloalkene.

In some embodiments, the ring is an aromatic ring. The term “aromatic”refers to a planar ring having a delocalized π-electron systemcontaining 4n+2π electrons, where n is an integer. Aromatic rings can beformed from five, six, seven, eight, nine, or more than nine atoms.Aromatics can be optionally substituted. The term “aromatic” includesboth carbocyclic aryl (e.g., phenyl) and heterocyclic aryl (or“heteroaryl” or “heteroaromatic”) groups (e.g., pyridine). The termincludes monocyclic or fused-ring polycyclic (i.e., rings which shareadjacent pairs of carbon atoms) groups.

In some embodiments, the ring is a heterocycle. The term “heterocycle”refers to heteroaromatic and heteroalicyclic groups containing one tofour heteroatoms each selected from O, S and N, wherein eachheterocyclic group has from 4 to 10 atoms in its ring system, and withthe proviso that the ring of said group does not contain two adjacent Oor S atoms. Non-aromatic heterocyclic groups include groups having only3 atoms in their ring system, but aromatic heterocyclic groups must haveat least 5 atoms in their ring system. The heterocyclic groups includebenzo-fused ring systems. An example of a 3-membered heterocyclic groupis aziridinyl. An example of a 4-membered heterocyclic group isazetidinyl (derived from azetidine). An example of a 5-memberedheterocyclic group is thiazolyl. An example of a 6-membered heterocyclicgroup is pyridyl, and an example of a 10-membered heterocyclic group isquinolinyl. Examples of non-aromatic heterocyclic groups arepyrrolidinyl, tetrahydrofuranyl, dihydrofuranyl, tetrahydrothienyl,tetrahydropyranyl, dihydropyranyl, tetrahydrothiopyranyl, piperidino,morpholino, thiomorpholino, thioxanyl, piperazinyl, azetidinyl,oxetanyl, thietanyl, homopiperidinyl, oxepanyl, thiepanyl, oxazepinyl,diazepinyl, thiazepinyl, 1,2,3,6-tetrahydropyridinyl, 2-pyrrolinyl,3-pyrrolinyl, indolinyl, 2H-pyranyl, 4H-pyranyl, dioxanyl,1,3-dioxolanyl, pyrazolinyl, dithianyl, dithiolanyl, dihydropyranyl,dihydrothienyl, dihydrofuranyl, pyrazolidinyl, imidazolinyl,imidazolidinyl, 3-azabicyclo[3.1.0]hexanyl, 3-azabicyclo[4.1.0]heptanyl,3H-indolyl and quinolizinyl. Examples of aromatic heterocyclic groupsare pyridinyl, imidazolyl, pyrimidinyl, pyrazolyl, triazolyl, pyrazinyl,tetrazolyl, furyl, thienyl, isoxazolyl, thiazolyl, oxazolyl,isothiazolyl, pyrrolyl, quinolinyl, isoquinolinyl, indolyl,benzimidazolyl, benzofuranyl, cinnolinyl, indazolyl, indolizinyl,phthalazinyl, pyridazinyl, triazinyl, isoindolyl, pteridinyl, purinyl,oxadiazolyl, thiadiazolyl, furazanyl, benzofurazanyl, benzothiophenyl,benzothiazolyl, benzoxazolyl, quinazolinyl, quinoxalinyl,naphthyridinyl, and furopyridinyl. The foregoing groups, may beC-attached or N-attached where such is possible. For instance, a groupderived from pyrrole may be pyrrol-1-yl (N-attached) or pyrrol-3-yl(C-attached). Further, a group derived from imidazole may beimidazol-1-yl or imidazol-3-yl (both N-attached) or imidazol-2-yl,imidazol-4-yl or imidazol-5-yl (all C-attached). The heterocyclic groupsinclude benzo-fused ring systems and ring systems substituted with oneor two oxo (═O) moieties such as pyrrolidin-2-one. Depending on thestructure, a heterocycle group can be a monoradical or a diradical(i.e., a heterocyclene group).

In some embodiments, the ring is fused. The term “fused” refers tostructures in which two or more rings share one or more bonds. In someembodiments, the ring is a dimer. In some embodiments, the ring is atrimer. In some embodiments, the ring is a substituted.

The term “carbocyclic” or “carbocycle” refers to a ring wherein each ofthe atoms forming the ring is a carbon atom. Carbocycle includes aryland cycloalkyl. The term thus distinguishes carbocycle from heterocycle(“heterocyclic”) in which the ring backbone contains at least one atomwhich is different from carbon (i.e., a heteroatom). Heterocycleincludes heteroaryl and heterocycloalkyl. Carbocycles and heterocyclescan be optionally substituted.

In some embodiments, the linker is substituted. The term “optionallysubstituted” or “substituted” means that the referenced group may besubstituted with one or more additional group(s) individually andindependently selected from C₁-C₆alkyl, C₃-C₈cycloalkyl, aryl,heteroaryl, C₂-C₆heteroalicyclic, hydroxy, C₁-C₆alkoxy, aryloxy,C₁-C₆alkylthio, arylthio, C₁-C₆alkylsulfoxide, arylsulfoxide,C₁-C₆alkylsulfone, arylsulfone, cyano, halo, C₂-C₈acyl, C₂-C₈acyloxy,nitro, C₁-C₆haloalkyl, C₁-C₆fluoroalkyl, and amino, includingC₁-C₆alkylamino, and the protected derivatives thereof. By way ofexample, an optional substituents may be LsRs, wherein each Ls isindependently selected from a bond, —O—, —C(═O)—, —S—, —S(═O)—,—S(═O)₂—, —NH—, —NHC(═O)—, —C(═O)NH—, S(═O)₂NH—, —NHS(═O)₂—, —OC(═O)NH—,—NHC(═O)O—, —(C₁-C₆alkyl)-, or —(C₂-C₆alkenyl)-; and each Rs isindependently selected from H, (C₁-C₄alkyl), (C₃-C₈cycloalkyl),heteroaryl, aryl, and C₁-C₆heteroalkyl. Optionally substitutednon-aromatic groups may be substituted with one or more oxo (═O). Theprotecting groups that may form the protective derivatives of the abovesubstituents are known to those of skill in the art.

In some embodiments, a selective delivery molecules disclosed hereincomprises a single of linker. Use of a single mechanism to mediateuptake of both imaging and therapeutic cargoes is particularly valuable,because imaging with noninjurious tracer quantities can be used to testwhether a subsequent therapeutic dose is likely to concentrate correctlyin the target tissue.

In some embodiments, a selective delivery molecules disclosed hereincomprises a plurality of linkers. Where a selective delivery moleculedisclosed herein includes multiple X linkages, separation of portion Afrom the other portions of the molecule requires cleavage of all Xlinkages. Cleavage of multiple X linkers may be simultaneous orsequential. Multiple X linkages may include X linkages having differentspecificities, so that separation of portion A from the other portionsof the molecule requires that more than one condition or environment(“extracellular signals”) be encountered by the molecule. Cleavage ofmultiple X X linkers thus serves as a detector of combinations of suchextracellular signals. For example, a selective delivery molecule mayinclude two linker portions Xa and Xb connecting basic portion B withacidic portion A. Both X linkersa and Xb must be cleaved before acidicportion A is separated from basic portion B allowing entry of portion Band cargo moiety C (if any) to enter a cell. It will be understood thata linker region may link to either a basic portion B or a cargo moiety Cindependently of another linker that may be present, and that, wheredesired, more than two linker regions X may be included.

Combinations of two or more X linkers may be used to further modulatethe targeting and delivery of molecules to desired cells, tissue orregions. Combinations of extracellular signals are used to widen ornarrow the specificity of the cleavage of X linkers if desired. Wheremultiple X linkers are linked in parallel, the specificity of cleavageis narrowed, since each X linker must be cleaved before portion A mayseparate from the remainder of the molecule. Where multiple X linkersare linked in series, the specificity of cleavage is broadened, sincecleavage on any one X linker allows separation of portion A from theremainder of the molecule. For example, in order to detect either aprotease OR hypoxia (i.e., to cleave X in the presence of eitherprotease or hypoxia), a X linker is designed to place theprotease-sensitive and reduction-sensitive sites in tandem, so thatcleavage of either would suffice to allow separation of the acidicportion A. Alternatively, in order to detect the presence of both aprotease AND hypoxia (i.e., to cleave X in the presence of both proteaseand hypoxia but not in the presence of only one alone), a X linker isdesigned to place the protease sensitive site between at least one pairof cysteines that are disulfide-bonded to each other. In that case, bothprotease cleavage and disulfide reduction are required in order to allowseparation of portion A.

Exemplary Selective Delivery Molecules

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-14.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-15.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-23.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-24.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-25.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-26.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-27.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-32.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-35.

Disclosed herein, in certain embodiments, are peptides according toPeptide P-3.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-14.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-15.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-23.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-24.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-25.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-26.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-27.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-32.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-35.

In some embodiments, the selective delivery molecule has a structureselected from: SDM-1, SDM-2, SDM-3, SDM-4, SDM-5, SDM-6, SDM-7, SDM-8,SDM-9, SDM-10, SDM-11, SDM-12, SDM-13, SDM-14, SDM-15, SDM-16, SDM-17,SDM-18, SDM-19, SDM-20, SDM-21, SDM-22, SDM-23, SDM-24, SDM-25, SDM-26,SDM-27, SDM-28, SDM-29, SDM-30, SDM-31, SDM-32, SDM-33, SDM-34, SDM-35,SDM-36, SDM-37, SDM-38, SDM-39, and SDM-40.

Further Modifications

In some embodiments, the targeting molecules of the present inventionare optionally conjugated to high molecular weight molecules thatincrease the multivalency and avidity of labeling. In some embodiments,the high molecular weight molecules are water-soluble polymers. Examplesof suitable water-soluble polymers include, but are not limited to,peptides, saccharides, poly(vinyls), poly(ethers), poly(amines),poly(carboxylic acids) and the like. In some embodiments, thewater-soluble polymer is dextran, polyethylene glycol (PEG),polyoxyalkylene, polysialic acid, starch, or hydroxyethyl starch. Anysuitable method is used to conjugate peptides to water-soluble polymers(see Hermanson G., Bioconjugate Techniques 2^(nd) Ed., Academic Press,Inc. 2008).

Pharmaceutical Compositions

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule of Formula I,having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a macromolecule; and    -   D_(A) and D_(B) are each independently selected from an imaging        agent and a therapeutic; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, the number of        basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence RLQLKL (SEQ ID NO: 11). In        some embodiments, X comprises the amino acid sequence RLQLK(Ac)        (SEQ ID NO: 12). In some embodiments, M is selected from a        protein, a natural polymer, a synthetic polymer, or a dendrimer.        In some embodiments, M is selected from dextran, a PEG polymer,        albumin, or a combination thereof. In some embodiments, M is a        PEG. In some embodiments, M is selected from PEG 5 kDa, PEG 12        kDa, PEG 20 kDa, PEG 30 kDa, and PEG40 kDa. In some embodiments,        D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other. In some embodiments,        D_(A) and D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and        D_(B) are Cy5 and IRDye750. In some embodiments, D_(A) and D_(B)        are Cy5 and IRDye800. In some embodiments, D_(A) and D_(B) are        Cy5 and ICG. In some embodiments, D_(A) and D_(B) are a        fluorescent moiety and a fluorescence-quenching moiety. In some        embodiments, the molecule of Formula I is: SDM-14, SDM-15,        SDM-23, SDM-24, SDM-25, SDM-26, SDM-27, SDM-32, or SDM-35.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule of Formula I,having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are each independently an imaging agent; and    -   wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, the number of        basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence PPRSFL (SEQ ID NO: 10). In        some embodiments, X comprises the amino acid sequence RLQLKL        (SEQ ID NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, D_(A) and D_(B) are a fluorescent        moiety and a fluorescence-quenching moiety. In some embodiments,        the molecule of Formula I is: SDM-14, SDM-15, SDM-23, SDM-24,        SDM-25, SDM-26, SDM-27, SDM-32; or SDM-35.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule of Formula I,having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 or 9 consecutive        glutamates (SEQ ID NO: 3);    -   B is a peptide with a sequence comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4); c_(A), c_(B), and c_(M) each        independently comprise 0-1 amino acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, c_(A), c_(B),        and c_(M) are each independently selected from any amino acid        having a free thiol group, any amino acid having a N-terminal        amine group, and any amino acid with a side chain capable of        forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently a 0-1 amino acid. In        some embodiments, c_(A), c_(B), and c_(M) are each independently        selected from D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and Cy7.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule of Formula I,having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 consecutive        glutamates (SEQ ID NO: 5);    -   B is a peptide with a sequence comprising 8 consecutive        arginines (SEQ ID NO: 6);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, X comprises        the amino acid sequence RPLALWRS (SEQ ID NO: 7). In some        embodiments, D_(A) and D_(B) are Cy5 and Cy7. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye750. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye800. In some        embodiments, D_(A) and D_(B) are Cy5 and ICG.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule of Formula I,having the structure:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 9 consecutive        glutamates (SEQ ID NO: 13);    -   B is a peptide with a sequence comprising 9 consecutive        arginines (SEQ ID NO: 14);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, X comprises        the amino acid sequence RPLALWRS (SEQ ID NO: 7). In some        embodiments, D_(A) and D_(B) are Cy5 and Cy7. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye750. In some        embodiments, D_(A) and D_(B) are Cy5 and IRDye800. In some        embodiments, D_(A) and D_(B) are Cy5 and ICG.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule according toSDM-14.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule according toSDM-15.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule according toSDM-23.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule according toSDM-24.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule according toSDM-25.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule according toSDM-26.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule according toSDM-27.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule according toSDM-32.

Disclosed herein, in certain embodiments, are pharmaceuticalcompositions comprising a selective delivery molecule according toSDM-35.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-14.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-15.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-23.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-24.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-25.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-26.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-27.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-32.

Disclosed herein, in certain embodiments, are selective deliverymolecules according to SDM-35.

Pharmaceutical compositions herein are formulated using one or morephysiologically acceptable carriers including excipients and auxiliarieswhich facilitate processing of the active agents into preparations whichare used pharmaceutically. Proper formulation is dependent upon theroute of administration chosen. A summary of pharmaceutical compositionsis found, for example, in Remington: The Science and Practice ofPharmacy, Nineteenth Ed (Easton, Pa.: Mack Publishing Company, 1995);Hoover, John E., Remington's Pharmaceutical Sciences, Mack PublishingCo., Easton, Pa. 1975; Liberman, H. A. and Lachman, L., Eds.,Pharmaceutical Dosage Forms, Marcel Decker, New York, N.Y., 1980; andPharmaceutical Dosage Forms and Drug Delivery Systems, Seventh Ed.(Lippincott Williams & Wilkins, 1999).

In certain embodiments, a pharmaceutical composition disclosed hereinfurther comprises a pharmaceutically acceptable diluent(s),excipient(s), or carrier(s). In some embodiments, the pharmaceuticalcompositions includes other medicinal or pharmaceutical agents,carriers, adjuvants, such as preserving, stabilizing, wetting oremulsifying agents, solution promoters, salts for regulating the osmoticpressure, and/or buffers. In addition, the pharmaceutical compositionsalso contain other therapeutically valuable substances.

In certain embodiments, a pharmaceutical composition disclosed herein isadministered to a subject by any suitable administration route,including but not limited to, parenteral (intravenous, subcutaneous,intraperitoneal, intramuscular, intravascular, intrathecal,intravitreal, infusion, or local) administration.

Formulations suitable for intramuscular, subcutaneous, peritumoral, orintravenous injection include physiologically acceptable sterile aqueousor non-aqueous solutions, dispersions, suspensions or emulsions, andsterile powders for reconstitution into sterile injectable solutions ordispersions. Examples of suitable aqueous and non-aqueous carriers,diluents, solvents, or vehicles including water, ethanol, polyols(propyleneglycol, polyethylene-glycol, glycerol, cremophor and thelike), suitable mixtures thereof, vegetable oils (such as olive oil) andinjectable organic esters such as ethyl oleate. Proper fluidity ismaintained, for example, by the use of a coating such as lecithin, bythe maintenance of the required particle size in the case ofdispersions, and by the use of surfactants. Formulations suitable forsubcutaneous injection also contain optional additives such aspreserving, wetting, emulsifying, and dispensing agents.

For intravenous injections, an active agent is optionally formulated inaqueous solutions, preferably in physiologically compatible buffers suchas Hank's solution, Ringer's solution, or physiological saline buffer.

Parenteral injections optionally involve bolus injection or continuousinfusion. Formulations for injection are optionally presented in unitdosage form, e.g., in ampoules or in multi dose containers, with anadded preservative. In some embodiments, the pharmaceutical compositiondescribed herein are in a form suitable for parenteral injection as asterile suspensions, solutions or emulsions in oily or aqueous vehicles,and contain formulatory agents such as suspending, stabilizing and/ordispersing agents. Pharmaceutical formulations for parenteraladministration include aqueous solutions of an active agent in watersoluble form. Additionally, suspensions are optionally prepared asappropriate oily injection suspensions.

In some embodiments, the pharmaceutical composition described herein isin unit dosage forms suitable for single administration of precisedosages. In unit dosage form, the formulation is divided into unit dosescontaining appropriate quantities of an active agent disclosed herein.In some embodiments, the unit dosage is in the form of a packagecontaining discrete quantities of the formulation. Non-limiting examplesare packaged tablets or capsules, and powders in vials or ampoules. Insome embodiments, aqueous suspension compositions are packaged insingle-dose non-reclosable containers. Alternatively, multiple-dosereclosable containers are used, in which case it is typical to include apreservative in the composition. By way of example only, formulationsfor parenteral injection are presented in unit dosage form, whichinclude, but are not limited to ampoules, or in multi dose containers,with an added preservative.

Methods of Use

The selective delivery molecules of Formula I allow the targeteddelivery of therapeutic agents and/or imaging agents to specific cellsand/or tissues. The molecules comprise a basic peptide sequence (B)which is designed to be transported across a cellular membrane, anacidic peptide sequence (A) which inhibits uptake of peptide B intocells, a linker X which is cleavable under specific conditions, cargomoieties (at least D_(A) and D_(B)) bound to peptides A and B, or X anda macromolecular carrier. In some embodiments, cleavage of the linker Xlinker frees peptide B from peptide A and allows the transport ofpeptide B (and any cargo attached thereto) across a cellular membrane.In some embodiments, the selective delivery molecules of Formula Ienable targeted delivery of one or more cargos (e.g., therapeutic agentsor imaging agents) to a cell tissue.

Disclosed herein, in certain embodiments, are methods of deliveringcargo to a tissue of interest, comprising contacting the tissue ofinterest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a macromolecule; and    -   D_(A) and D_(B) are each independently selected from an imaging        agent and a therapeutic; and wherein [c_(M)-M] is bound to at        any position on A or X, [D_(A)-c_(A)] is bound to any amino acid        on A, and [c_(B)-D_(B)] is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, the number of        basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence RLQLKL (SEQ ID NO: 11). In        some embodiments, X comprises the amino acid sequence RLQLK(Ac)        (SEQ ID NO: 12). In some embodiments, M is selected from a        protein, a natural polymer, a synthetic polymer, or a dendrimer.        In some embodiments, M is selected from dextran, a PEG polymer,        albumin, or a combination thereof. In some embodiments, M is a        PEG. In some embodiments, M is selected from PEG 5 kDa, PEG 12        kDa, PEG 20 kDa, PEG 30 kDa, and PEG40 kDa. In some embodiments,        D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other. In some embodiments,        D_(A) and D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and        D_(B) are Cy5 and IRDye750. In some embodiments, D_(A) and D_(B)        are Cy5 and IRDye800. In some embodiments, D_(A) and D_(B) are        Cy5 and ICG. In some embodiments, D_(A) and D_(B) are a        fluorescent moiety and a fluorescence-quenching moiety. In some        embodiments, the molecule of Formula I is: SDM-14, SDM-15,        SDM-23, SDM-24, SDM-25, SDM-26, SDM-27, SDM-32, or SDM-35.

Disclosed herein, in certain embodiments, are methods of deliveringcargo to a tissue of interest, comprising contacting the tissue ofinterest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are each independently selected from imaging        agents and therapeutic agents; and    -   wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, the number of        basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence PPRSFL (SEQ ID NO: 10). In        some embodiments, X comprises the amino acid sequence RLQLKL        (SEQ ID NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12).

Disclosed herein, in certain embodiments, are methods of deliveringcargo to a tissue of interest, comprising contacting the tissue ofinterest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 or 9 consecutive        glutamates (SEQ ID NO: 3);    -   B is a peptide with a sequence comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are independently selected from imagining agents        and therapeutic agents; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, c_(A), c_(B),        and c_(M) are each independently a 0-1 amino acid. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from any amino acid having a free thiol group, any        amino acid having a N-terminal amine group, and any amino acid        with a side chain capable of forming an oxime or hydrazone bond        upon reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1).

Disclosed herein, in certain embodiments, are methods of deliveringcargo to a tissue of interest, comprising contacting the tissue ofinterest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 consecutive        glutamates (SEQ ID NO: 5);    -   B is a peptide with a sequence comprising 8 consecutive        arginines (SEQ ID NO: 6);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are independently selected from imaging agents        and therapeutic agents; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, X comprises        the amino acid sequence RPLALWRS (SEQ ID NO: 7).

Disclosed herein, in certain embodiments, are methods of deliveringcargo to a tissue of interest, comprising contacting the tissue ofinterest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 9 consecutive        glutamates (SEQ ID NO: 13);    -   B is a peptide with a sequence comprising 9 consecutive        arginines (SEQ ID NO: 14);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are independently selected from imaging agents        and therapeutic agents; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, X comprises        the amino acid sequence RPLALWRS (SEQ ID NO: 7).

Tissue of Interest

In som embodiments, the tissue of interest is casncerous tissue (or,cancer). In some embodiments, the cancerous tissue is: breast cancertissue, colon cancer tissue, squamous cell carcinoma tissue, prostatecancer tissue, melanoma tissue, or thyroid cancer tissue. In someembodiments, the cancerous tissue is breast cancer tissue. In someembodiments, the cancerous tissue is colon cancer tissue.

In some embodiments, the cancer is AIDS-related cancers (e.g.,AIDS-related lymphoma), anal cancer, basal cell carcinoma, bile ductcancer (e.g., extrahepatic), bladder cancer, bone cancer, (osteosarcomaand malignant fibrous histiocytoma), breast cancer, cervical cancer,colon cancer, colorectal cancer, endometrial cancer (e.g., uterinecancer), ependymoma, esophageal cancer, eye cancer (e.g., intraocularmelanoma and retinoblastoma), gastric (stomach) cancer, germ cell tumor,(e.g., extracranial, extragonadal, ovarian), head and neck cancer,leukemia, lip and oral cavity cancer, liver cancer, lung cancer (e.g.,small cell lung cancer, non-small cell lung cancer, adenocarcinoma ofthe lung, and squamous carcinoma of the lung), ovarian cancer,pancreatic cancer, pituitary tumor, prostate cancer, renal cancer, skincancer, small intestine cancer, squamous cell cancer, testicular cancer,throat cancer, thyroid cancer, urethral cancer, and post-transplantlymphoproliferative disorder (PTLD).

In some embodiments, the cancer is a lymphoid cancer (e.g., lymphoma).

In some embodiments, the cancer is a B-cell cancer. In some embodiments,the cancer is precursor B-cell cancers (e.g., precursor B-lymphoblasticleukemia/lymphoma) and peripheral B-cell cancers (e.g., B-cell chroniclymphocytic leukemia/prolymphocytic leukemia/small lymphocytic lymphoma(small lymphocytic (SL) NHL), lymphoplasmacytoid lymphoma/immunocytoma,mantel cell lymphoma, follicle center lymphoma, follicular lymphoma(e.g., cytologic grades: I (small cell), II (mixed small and largecell), III (large cell) and/or subtype: diffuse and predominantly smallcell type), low grade/follicular non-Hodgkin's lymphoma (NHL),intermediate grade/follicular NHL, marginal zone B-cell lymphoma (e.g.,extranodal (e.g., MALT-type+/−monocytoid B cells) and/or Nodal (e.g.,+/−monocytoid B cells)), splenic marginal zone lymphoma (e.g.,+/−villous lymphocytes), Hairy cell leukemia, plasmacytoma/plasma cellmyeloma (e.g., myeloma and multiple myeloma), diffuse large B-celllymphoma (e.g., primary mediastinal (thymic) B-cell lymphoma),intermediate grade diffuse NHL, Burkitt's lymphoma, High-grade B-celllymphoma, Burkitt-like, high grade immunoblastic NHL, high gradelymphoblastic NHL, high grade small non-cleaved cell NHL, bulky diseaseNHL, AIDS-related lymphoma, and Waldenstrom's macroglobulinemia).

In some embodiments, the cancer is a T-cell and/or putative NK-cellcancer. In some embodiments, the cancer is precursor T-cell cancer(precursor T-lymphoblastic lymphoma/leukemia) and peripheral T-cell andNK-cell cancers (e.g., T-cell chronic lymphocyticleukemia/prolymphocytic leukemia, and large granular lymphocyte leukemia(LGL) (e.g., T-cell type and/or NK-cell type), cutaneous T-cell lymphoma(e.g., mycosis fungoides/Sezary syndrome), primary T-cell lymphomasunspecified (e.g., cytological categories (e.g., medium-sized cell,mixed medium and large cell), large cell, lymphoepitheloid cell, subtypehepatosplenic γδ T-cell lymphoma, and subcutaneous panniculitic T-celllymphoma), angioimmunoblastic T-cell lymphoma (AILD), angiocentriclymphoma, intestinal T-cell lymphoma (e.g., +/−enteropathy associated),adult T-cell lymphoma/leukemia (ATL), anaplastic large cell lymphoma(ALCL) (e.g., CD30+, T- and null-cell types), anaplastic large-celllymphoma, and Hodgkin's like).

In some embodiments, the cancer is Hodgkin's disease.

In some embodiments, the cancer is leukemia. In some embodiments, thecancer is chronic myelocytic I (granulocytic) leukemia, chronicmyelogenous, and chronic lymphocytic leukemia (CLL), acute lymphoblasticleukemia (ALL), acute myeloid leukemia, acute lymphocytic leukemia, andacute myelocytic leukemia (e.g., myeloblastic, promyelocytic,myelomonocytic, monocytic, and erythroleukemia).

In some embodiments, the cancer is a liquid tumor or plasmacytoma. Insome embodiments, the cancer is extramedullary plasmacytoma, a solitarymyeloma, and multiple myeloma. In some embodiments, the plasmacytoma ismultiple myeloma.

In some embodiments, the cancer is lung cancer.

In some embodiments, the cancer is prostate cancer. In some embodiments,the prostate cancer is an adenocarcinoma. In some embodiments, theprostate cancer is a sarcoma, neuroendocrine tumor, small cell cancer,ductal cancer, or a lymphoma. In some embodiments, the prostate canceris stage A prostate cancer (the cancer cannot be felt during a rectalexam). In some embodiments, the prostate cancer is stage B prostatecancer (i.e., the tumor involves more tissue within the prostate, it canbe felt during a rectal exam, or it is found with a biopsy that is donebecause of a high PSA level). In some embodiments, the prostate canceris stage C prostate cancer (i.e., the cancer has spread outside theprostate to nearby tissues). In some embodiments, the prostate cancer isstage D prostate cancer. In some embodiments, the prostate cancer isandrogen independent prostate cancer (AIPC). In some embodiments, theprostate cancer is androgen dependent prostate cancer. In someembodiments, the prostate cancer is refractory to hormone therapy. Insome embodiments, the prostate cancer is substantially refractory tohormone therapy. In some embodiments, the prostate cancer is refractoryto chemotherapy. In some embodiments, the prostate cancer is metastaticprostate cancer. In some embodiments, the individual is a human who hasa gene, genetic mutation, or polymorphism associated with prostatecancer (e.g., RNASEL/HPC1, ELAC2/HPC2, SR-A/MSR1, CHEK2, BRCA2, PON1,OGG1, MIC-1, TLR4, and PTEN) or has one or more extra copies of a geneassociated with prostate cancer. In some embodiments, the prostatecancer is HER2 positive. In some embodiments, the prostate cancer isHER2 negative.

In some embodiments, the cancer has metastasized and is characterized bycirculating tumor cells.

Imaging Uses

The selective delivery molecules of Formula I allow the targeteddelivery of imaging agents to specific cells and/or tissues (e.g.,cancerous tissues). The molecules comprise a basic peptide sequence (B)which is designed to be transported across a cellular membrane orretained by tissue, an acidic peptide sequence (A) which inhibits uptakeand retention of peptide B into cells, a linker X which is cleavableunder specific conditions, imaging moieties bound to peptides A and B,or X and a macromolecular carrier. In some embodiments, cleavage of thelinker X linker frees peptide B from peptide A and allows the transportof peptide B (and any imaging moieties attached thereto) across acellular membrane or retention of B to tissue. In some embodiments, theselective delivery molecules of Formula I enable targeted delivery ofone or more imaging agents to a cell or tissue. In some embodiments,targeted delivery of an imaging agent to a cell or tissue enables amedical professional to visualize/image a specific tissue.

Disclosed herein, in certain embodiments, are methods of deliveringimaging agents to a tissue of interest, comprising contacting the tissueof interest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are each independently an imaging agent; and    -   wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, the number of        basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence PPRSFL (SEQ ID NO: 10). In        some embodiments, X comprises the amino acid sequence RLQLKL        (SEQ ID NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, D_(A) and D_(B) are a fluorescent        moiety and a fluorescence-quenching moiety.

Disclosed herein, in certain embodiments, are methods of deliveringimaging agents to a tissue of interest, comprising contacting the tissueof interest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 or 9 consecutive        glutamates (SEQ ID NO: 3);    -   B is a peptide with a sequence comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are each independently an imaging agent; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, c_(A), c_(B),        and c_(M) are each independently a 0-1 amino acid. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from any amino acid having a free thiol group, any        amino acid having a N-terminal amine group, and any amino acid        with a side chain capable of forming an oxime or hydrazone bond        upon reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence RPLALWRS (SEQ        ID NO: 7). In some embodiments, X comprises the amino acid        sequence DPRSFL (SEQ ID NO: 9). In some embodiments, X comprises        the amino acid sequence PPRSFL (SEQ ID NO: 10). In some        embodiments, X comprises the amino acid sequence RLQLKL (SEQ ID        NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, D_(A) and D_(B) are a fluorescent        moiety and a fluorescence-quenching moiety.

Disclosed herein, in certain embodiments, are methods of deliveringimaging agents to a tissue of interest, comprising contacting the tissueof interest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 consecutive        glutamates (SEQ ID NO: 5);    -   B is a peptide with a sequence comprising 8 consecutive        arginines (SEQ ID NO: 6);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are each independently an imaging agent; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence RPLALWRS (SEQ        ID NO: 7). In some embodiments, X comprises the amino acid        sequence DPRSFL (SEQ ID NO: 9). In some embodiments, X comprises        the amino acid sequence PPRSFL (SEQ ID NO: 10). In some        embodiments, X comprises the amino acid sequence RLQLKL (SEQ ID        NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, D_(A) and D_(B) are a fluorescent        moiety and a fluorescence-quenching moiety.

Disclosed herein, in certain embodiments, are methods of deliveringimaging agents to a tissue of interest, comprising contacting the tissueof interest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 9 consecutive        glutamates (SEQ ID NO: 13);    -   B is a peptide with a sequence comprising 9 consecutive        arginines (SEQ ID NO: 14);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are each independently an imaging agent; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence RPLALWRS (SEQ        ID NO: 7). In some embodiments, X comprises the amino acid        sequence DPRSFL (SEQ ID NO: 9). In some embodiments, X comprises        the amino acid sequence PPRSFL (SEQ ID NO: 10). In some        embodiments, X comprises the amino acid sequence RLQLKL (SEQ ID        NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, D_(A) and D_(B) are a fluorescent        moiety and a fluorescence-quenching moiety.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other; and    -   wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, the number of        basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence PPRSFL (SEQ ID NO: 10). In        some embodiments, X comprises the amino acid sequence RLQLKL        (SEQ ID NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, D_(A) and D_(B) are a fluorescent        moiety and a fluorescence-quenching moiety.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 or 9 consecutive        glutamates (SEQ ID NO: 3);    -   B is a peptide with a sequence comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, c_(A), c_(B),        and c_(M) are each independently a 0-1 amino acid. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from any amino acid having a free thiol group, any        amino acid having a N-terminal amine group, and any amino acid        with a side chain capable of forming an oxime or hydrazone bond        upon reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence RPLALWRS (SEQ        ID NO: 7). In some embodiments, X comprises the amino acid        sequence DPRSFL (SEQ ID NO: 9). In some embodiments, X comprises        the amino acid sequence PPRSFL (SEQ ID NO: 10). In some        embodiments, X comprises the amino acid sequence RLQLKL (SEQ ID        NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B)        are Cy5 and Cy7.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 consecutive        glutamates (SEQ ID NO: 5);    -   B is a peptide with a sequence comprising 8 consecutive        arginines (SEQ ID NO: 6);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of undergoing Försters/fluorescence        resonance energy transfer with the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence RPLALWRS (SEQ        ID NO: 7). In some embodiments, X comprises the amino acid        sequence DPRSFL (SEQ ID NO: 9). In some embodiments, X comprises        the amino acid sequence PPRSFL (SEQ ID NO: 10). In some        embodiments, X comprises the amino acid sequence RLQLKL (SEQ ID        NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B)        are Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5        and ICG.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 9 consecutive        glutamates (SEQ ID NO: 13);    -   B is a peptide with a sequence comprising 9 consecutive        arginines (SEQ ID NO: 14);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent        moieties that are capable of    -   undergoing Försters/fluorescence resonance energy transfer with        the other; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from any amino acid having a free thiol        group, any amino acid having a N-terminal amine group, and any        amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence RPLALWRS (SEQ        ID NO: 7). In some embodiments, X comprises the amino acid        sequence DPRSFL (SEQ ID NO: 9). In some embodiments, X comprises        the amino acid sequence PPRSFL (SEQ ID NO: 10). In some        embodiments, X comprises the amino acid sequence RLQLKL (SEQ ID        NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B)        are Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5        and ICG.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with SDM-14.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with SDM-15.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with SDM-23.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with SDM-24.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with SDM-25.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with SDM-26.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother o to a tissue of interest, comprising contacting the tissue ofinterest with SDM-27.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with SDM-32.

Disclosed herein, in certain embodiments, are methods of delivering apair of acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother to a tissue of interest, comprising contacting the tissue ofinterest with SDM-35.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising:

(a) administering to the individual a molecule of Formula I thatlocalizes to the tissue of interest in the individual,

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)];   Formula I

-   -   wherein,        -   X is a cleavable linker;        -   A is a peptide with a sequence comprising 5 to 9 acidic            amino acids;        -   B is a peptide with a sequence comprising 7 to 9 basic amino            acids;        -   c_(A), c_(B), and c_(M) each independently comprise 0-1            amino acid;        -   M is a polyethylene glycol (PEG) polymer; and        -   D_(A) and D_(B) are each independently an imaging agent; and    -   wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B; and        (b) visualizing at least one of the imaging agents.        In some embodiments, the tissue is cancerous. In some        embodiments, the cancerous tissue is: breast cancer tissue,        colorectal cancer tissue, squamous cell carcinoma tissue,        prostate cancer tissue, melanoma tissue, or thyroid cancer        tissue. In some embodiments, the cancerous cell or tissue is        breast cancer tissue. In some embodiments, the cancerous cell or        tissue is colon cancer tissue. In some embodiments, the method        further comprises surgically removing the tissue of interest        from the individual. In some embodiments, the surgical margin        surrounding the tissue of interest is decreased. In some        embodiments, the method further comprises preparing a tissue        sample from the removed cell or tissue of interest. In some        embodiments, the method further comprises staging the cancerous        tissue. In some embodiments, A and B do not have an equal number        of acidic and basic amino acids. In some embodiments, the number        of basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence PPRSFL (SEQ ID NO: 10). In        some embodiments, X comprises the amino acid sequence RLQLKL        (SEQ ID NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are a pair of acceptor and donor fluorescent moieties        that are capable of undergoing Försters/fluorescence resonance        energy transfer with the other. In some embodiments, D_(A) and        D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are Cy5        and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5 and        ICG. In some embodiments, the method further comprises        visualizing Försters/fluorescence resonance energy transfer        between D_(A) and D_(B). In some embodiments, D_(A) and D_(B)        are a fluorescent moiety and a fluorescence-quenching moiety. In        some embodiments, the molecule is chosen from: SDM-14, SDM-15,        SDM-23, SDM-24, SDM-25, SDM-26, SDM-27, SDM-32, and SDM-35.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising:

(a) administering to the individual a molecule of Formula I thatlocalizes to the tissue of interest in the individual,

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

-   -   wherein,        -   X is a peptide linker cleavable by a matrix            metalloproteinase;        -   A is a peptide with a sequence comprising 5 or 9 consecutive            glutamates (SEQ ID NO: 3);        -   B is a peptide with a sequence comprising 8 or 9 consecutive            arginines (SEQ ID NO: 4);        -   c_(A), c_(B), and c_(M) each independently comprise 0-1            amino acid;        -   M is a polyethylene glycol (PEG) polymer; and        -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent            moieties that are capable of undergoing            Försters/fluorescence resonance energy transfer with the            other; and    -   wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B; and        (b) visualizing at least one of the imaging agents.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, c_(A), c_(B),        and c_(M) are each independently a 0-1 amino acid. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from any amino acid having a free thiol group, any        amino acid having a N-terminal amine group, and any amino acid        with a side chain capable of forming an oxime or hydrazone bond        upon reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence RPLALWRS (SEQ        ID NO: 7). In some embodiments, X comprises the amino acid        sequence DPRSFL (SEQ ID NO: 9). In some embodiments, X comprises        the amino acid sequence PPRSFL (SEQ ID NO: 10). In some        embodiments, X comprises the amino acid sequence RLQLKL (SEQ ID        NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B)        are Cy5 and Cy7.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising:

(a) administering to the individual a molecule of Formula I thatlocalizes to the tissue of interest in the individual:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

-   -   wherein,        -   X is a peptide linker cleavable by a matrix            metalloproteinase;        -   A is a peptide with a sequence comprising 5 consecutive            glutamates (SEQ ID NO: 5);        -   B is a peptide with a sequence comprising 8 consecutive            arginines (SEQ ID NO: 6);        -   c_(A), c_(B), and c_(M) each independently comprise 0-1            amino acid;        -   M is a polyethylene glycol (PEG) polymer; and        -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent            moieties that are capable of undergoing            Försters/fluorescence resonance energy transfer with the            other; and    -   wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B; and        (b) visualizing at least one of the imaging agents.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence RPLALWRS (SEQ        ID NO: 7). In some embodiments, X comprises the amino acid        sequence DPRSFL (SEQ ID NO: 9). In some embodiments, X comprises        the amino acid sequence PPRSFL (SEQ ID NO: 10). In some        embodiments, X comprises the amino acid sequence RLQLKL (SEQ ID        NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B)        are Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5        and ICG.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising:

(a) administering to the individual a molecule of Formula I thatlocalizes to the tissue of interest in the individual:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

-   -   wherein,        -   X is a peptide linker cleavable by a matrix            metalloproteinase;        -   A is a peptide with a sequence comprising 9 consecutive            glutamates (SEQ ID NO: 13);        -   B is a peptide with a sequence comprising 9 consecutive            arginines (SEQ ID NO: 14);        -   c_(A), c_(B), and c_(M) each independently comprise 0-1            amino acid;        -   M is a polyethylene glycol (PEG) polymer; and        -   D_(A) and D_(B) are a pair of acceptor and donor fluorescent            moieties that are capable of undergoing            Försters/fluorescence resonance energy transfer with the            other; and    -   wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B; and        (b) visualizing at least one of the imaging agents.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence RPLALWRS (SEQ        ID NO: 7). In some embodiments, X comprises the amino acid        sequence DPRSFL (SEQ ID NO: 9). In some embodiments, X comprises        the amino acid sequence PPRSFL (SEQ ID NO: 10). In some        embodiments, X comprises the amino acid sequence RLQLKL (SEQ ID        NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, D_(A)        and D_(B) are Cy5 and Cy7. In some embodiments, D_(A) and D_(B)        are Cy5 and IRDye750. In some embodiments, D_(A) and D_(B) are        Cy5 and IRDye800. In some embodiments, D_(A) and D_(B) are Cy5        and ICG.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising,comprising (a) administering SDM-14 to the individual, and (b)visualizing at least one of the imaging agents.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising,comprising (a) administering SDM-15 to the individual, and (b)visualizing at least one of the imaging agents.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising,comprising (a) administering SDM-23 to the individual, and (b)visualizing at least one of the imaging agents.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising,comprising (a) administering SDM-24 to the individual, and (b)visualizing at least one of the imaging agents.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising,comprising (a) administering SDM-25 to the individual, and (b)visualizing at least one of the imaging agents.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising,comprising (a) administering SDM-26 to the individual, and (b)visualizing at least one of the imaging agents.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising,comprising (a) administering SDM-27 to the individual, and (b)visualizing at least one of the imaging agents.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising,comprising (a) administering SDM-32 to the individual, and (b)visualizing at least one of the imaging agents.

Disclosed herein, in certain embodiments, are methods of visualizing atissue of interest in an individual in need thereof, comprising,comprising (a) administering SDM-35 to the individual, and (b)visualizing at least one of the imaging agents.

In some embodiments, targeted delivery of an imaging agent to a cell ortissue enables a medical professional to visualize/image a specifictissue (e.g., cancerous tissue). In some embodiments, targeted deliveryof an imaging agent to a cell or tissue enables a medical professionalto remove (or, surgically excise) the tissue of interest (e.g.,cancerous tissue). In some embodiments, targeted delivery of an imagingagent to a cell or tissue enables a medical professional to remove (or,surgically excise) the tissue of interest (e.g., cancerous tissue) witha decrease in surgical margins. In some embodiments, targeted deliveryof an imaging agent to a cell or tissue enables a medical professionalto remove (or, surgically excise) a tumor/cancerous tissue and decreasesthe chance that some of the tumor/cancerous tissue will not be removed.In some embodiments, targeted delivery of an imaging agent to a cell ortissue enables a medical professional to maximally debulk atumor/cancerous tissue. In some embodiments, targeted delivery of animaging agent to cancerous breast tissue decreases the chances of anunnecessary operations and re-operations.

In some embodiments, targeted delivery of an imaging agent to a cell ortissue enables a medical professional to more accurately sample (e.g.,biopsy (e.g., excision biopsy, incision, biopsy, aspiration biopsy, orneedle biopsy)) tissue of interest (e.g., cancerous tissue). In someembodiments, targeted delivery of an imaging agent to a cell or tissueenables a medical professional to visualize/image a specific tissue(e.g., cancerous tissue) within an excised tissue containing healthytissue. Enabling identification of target tissue (e.g., canceroustissue) can guide the pathologist on where to section of pathologicalevaluation and decreases the chances of a pathologist missing unhealthytissue (e.g., cancerous tissue) and sampling healthy tissue which mayproduce a false negative. In some embodiments, tissue (e.g., canceroustissue) removed following use of a compound of Formula I is used toprepare a pathology section or slide. In some embodiments, canceroustissue removed following use of a compound of Formula I is used toprepare a pathology section or slide which is used to diagnose a tissueas malignant or benign.

In some embodiments, targeted delivery of an imaging agent to cancerousbreast tissue enables a medical professional to accurately stage cancerenabling medical treatment decisions. In some embodiments, targeteddelivery of an imaging agent to cancerous tissue enables a medicalprofessional to observe the size of a tumor (cancerous tissue) or thespread (e.g., metastatic lesions) of cancerous tissue. In someembodiments, targeted delivery of an imaging agent to a cell or tissueenables a medical professional to design an efficacious treatmentregimen.

In some embodiments, a selective delivery molecule according to FormulaI comprising an imaging agent is employed in guided surgery. In someembodiments, the selective delivery molecule preferentially localized tocancerous, or other pathological tissues with up-regulated proteaseactivity (e.g. tissues undergoing inflammatory response). In someembodiments, a selective delivery molecule according to Formula Icomprising an imaging agent is employed in a guided surgery to removecolorectal cancer. In some embodiments, guided surgery employing theselective delivery molecule allows a surgeon to excise as little healthy(i.e., non-cancerous) tissue as possible. In some embodiments, guidedsurgery employing the selective delivery molecule allows a surgeon tovisualize and excise more cancerous tissue than the surgeon would havebeen able to excise without the presence of the selective deliverymolecule. In some embodiments, the surgery is fluorescence-guidedsurgery.

Imaging Agents

In some embodiments, an imaging agent is a dye. In some embodiments, animaging agent is a fluorescent moiety. In some embodiments, afluorescent moiety is selected from: a fluorescent protein, afluorescent peptide, a fluorescent dye, a fluorescent material or acombination thereof.

All fluorescent moieties are encompassed within the term “fluorescentmoiety.” Specific examples of fluorescent moieties given herein areillustrative and are not meant to limit the fluorescent moieties for usewith the targeting molecules disclosed herein.

Examples of fluorescent dyes include, but are not limited to, xanthenes(e.g., rhodamines, rhodols and fluoresceins, and their derivatives);bimanes; coumarins and their derivatives (e.g., umbelliferone andaminomethyl coumarins); aromatic amines (e.g., dansyl; squarate dyes);benzofurans; fluorescent cyanines; indocarbocyanines; carbazoles;dicyanomethylene pyranes; polymethine; oxabenzanthrane; xanthene;pyrylium; carbostyl; perylene; acridone; quinacridone; rubrene;anthracene; coronene; phenanthrecene; pyrene; butadiene; stilbene;porphyrin; pthalocyanine; lanthanide metal chelate complexes; rare-earthmetal chelate complexes; and derivatives of such dyes.

Examples of fluorescein dyes include, but are not limited to,5-carboxyfluorescein, fluorescein-5-isothiocyanate,fluorescein-6-isothiocyanate and 6-carboxyfluorescein.

Examples of rhodamine dyes include, but are not limited to,tetramethylrhodamine-6-isothiocyanate, 5-carboxytetramethylrhodamine,5-carboxy rhodol derivatives, tetramethyl and tetraethyl rhodamine,diphenyldimethyl and diphenyldiethyl rhodamine, dinaphthyl rhodamine,rhodamine 101 sulfonyl chloride (sold under the tradename of TEXASRED®).

Examples of cyanine dyes include, but are not limited to, Cy3, Cy3B,Cy3.5, Cy5, Cy5.5, Cy7, IRDYE680, Alexa Fluor 750, IRDye800CW, ICG.

Examples of fluorescent peptides include GFP (Green Fluorescent Protein)or derivatives of GFP (e.g., EBFP, EBFP2, Azurite, mKalamal, ECFP,Cerulean, CyPet, YFP, Citrine, Venus, YPet).

Fluorescent labels are detected by any suitable method. For example, afluorescent label may be detected by exciting the fluorochrome with theappropriate wavelength of light and detecting the resultingfluorescence, e.g., by microscopy, visual inspection, via photographicfilm, by the use of electronic detectors such as charge coupled devices(CCDs), photomultipliers, etc.

In some embodiments, the imaging agent is labeled with apositron-emitting isotope (e.g., ¹⁸F) for positron emission tomography(PET), gamma-ray isotope (e.g., ^(99m)Tc) for single photon emissioncomputed tomography (SPECT), or a paramagnetic molecule or nanoparticle(e.g., Gd³⁺ chelate or coated magnetite nanoparticle) for magneticresonance imaging (MRI).

In some embodiments, the imaging agent is labeled with: a gadoliniumchelate, an iron oxide particle, a super paramagnetic iron oxideparticle, an ultra small paramagnetic particle, a manganese chelate orgallium containing agent.

Examples of gadolinium chelates include, but are not limited todiethylene triamine pentaacetic acid (DTPA),1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA), and1,4,7-triazacyclononane-N,N′,N″-triacetic acid (NOTA).

In some embodiments, the imaging agent is a near-infrared fluorophorefor near-infra red (near-IR) imaging, a luciferase (firefly, bacterial,or coelenterate) or other luminescent molecule for bioluminescenceimaging, or a perfluorocarbon-filled vesicle for ultrasound.

In some embodiments, the imaging agent is a nuclear probe. In someembodiments, the imaging agent is a SPECT or PET radionuclide probe. Insome embodiments, the radionuclide probe is selected from: a technetiumchelate, a copper chelate, a radioactive fluorine, a radioactive iodine,a indiuim chelate.

Examples of Tc chelates include, but are not limited to HYNIC, DTPA, andDOTA.

In some embodiments, the imaging agent contains a radioactive moiety,for example a radioactive isotope such as ²¹¹At, ¹³¹I, ¹²⁵I, ⁹⁰Y, ¹⁸⁶Re,¹⁸⁸Re, ¹⁵³Sm, ²¹²Bi, ³²P, ⁶⁴Cu radioactive isotopes of Lu, and others.

Therapeutic Uses

The selective delivery molecules of Formula I allow the targeteddelivery of therapeutic agents to specific cells and/or tissues (e.g.,cancerous tissues). The molecules comprise a basic peptide sequence (B)which is designed to be transported across a cellular membrane, anacidic peptide sequence (A) which inhibits uptake of peptide B intocells, a linker X which is cleavable under specific conditions,therapeutic agents bound to peptides A and B, or X and a macromolecularcarrier. In some embodiments, cleavage of the linker X linker freespeptide B from peptide A and allows the transport of peptide B (and anytherapeutic agents attached thereto) across a cellular membrane. In someembodiments, the selective delivery molecules of Formula I enabletargeted delivery of one or more therapeutic agents to a cell or tissue.In some embodiments, targeted delivery of a therapeutic agent to a cellor tissue enables a medical professional to treat a specific tissue.

Disclosed herein, in certain embodiments, are methods of delivering atherapeutic agent to a tissue of interest, comprising contacting thetissue of interest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a cleavable linker;    -   A is a peptide with a sequence comprising 5 to 9 acidic amino        acids;    -   B is a peptide with a sequence comprising 7 to 9 basic amino        acids;    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   at least one of D_(A) and D_(B) is independently a therapeutic        agent; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, the number of        basic amino acids in B is greater than the number of acidic        amino acids in A. In some embodiments, A is a peptide comprising        5 or 9 consecutive glutamates (SEQ ID NO: 3). In some        embodiments, B is a peptide comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4). In some embodiments, A is a peptide        comprising 5 or 9 consecutive glutamates (SEQ ID NO: 3) and B is        a peptide comprising 8 or 9 consecutive arginines (SEQ ID NO:        4). In some embodiments, A is a peptide comprising 5 consecutive        glutamates (SEQ ID NO: 5) and B is a peptide comprising 8        consecutive arginines (SEQ ID NO: 6). In some embodiments,        c_(A), c_(B), and c_(M) are each independently a 0-1 amino acid.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from a naturally-occurring amino acid or        a non-naturally-occurring amino acid. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a D        amino acid, a L amino acid, an α-amino acid, a β-amino acid, or        a γ-amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from any amino acid having a free        thiol group, any amino acid having a N-terminal amine group, and        any amino acid with a side chain capable of forming an oxime or        hydrazone bond upon reaction with a hydroxylamine or hydrazine        group. In some embodiments, c_(A), c_(B), and c_(M) are each        independently selected from D-cysteine, D-glutamate, lysine, and        para-4-acetyl L-phenylalanine. In some embodiments, c_(B) is any        amino acid having a free thiol group. In some embodiments, c_(B)        is D-cysteine. In some embodiments, c_(A) is any amino acid        having a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine. In some embodiments, X is        cleavable by a protease. In some embodiments, X is cleavable by        a matrix metalloproteinase. In some embodiments, X comprises an        amino acid sequence that is cleavable by MMP2, MMP7, MMP9, or        MMP14. In some embodiments, X comprises a peptide linkage. In        some embodiments, X comprises an amino acid sequence selected        from: PLGLAG (SEQ ID NO: 2), PLG-C(me)-AG (SEQ ID NO: 1),        RPLALWRS (SEQ ID NO: 7), ESPAYYTA (SEQ ID NO: 8), DPRSFL (SEQ ID        NO: 9), PPRSFL (SEQ ID NO: 10), RLQLKL (SEQ ID NO: 11), and        RLQLK(Ac) (SEQ ID NO: 12). In some embodiments, X comprises the        amino acid sequence PLGLAG (SEQ ID NO: 2). In some embodiments,        X comprises the amino acid sequence PLG-C(me)-AG (SEQ ID NO: 1).        In some embodiments, X comprises the amino acid sequence        RPLALWRS (SEQ ID NO: 7). In some embodiments, X comprises the        amino acid sequence DPRSFL (SEQ ID NO: 9). In some embodiments,        X comprises the amino acid sequence PPRSFL (SEQ ID NO: 10). In        some embodiments, X comprises the amino acid sequence RLQLKL        (SEQ ID NO: 11). In some embodiments, X comprises the amino acid        sequence RLQLK(Ac) (SEQ ID NO: 12).

Disclosed herein, in certain embodiments, are methods of delivering atherapeutic agent to a tissue of interest, comprising contacting thetissue of interest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 or 9 consecutive        glutamates (SEQ ID NO: 3);    -   B is a peptide with a sequence comprising 8 or 9 consecutive        arginines (SEQ ID NO: 4); c_(A), c_(B), and c_(M) each        independently comprise 0-1 amino acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   at least one of D_(A) and D_(B) is independently a therapeutic        agent; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, A and B do not have an equal number of        acidic and basic amino acids. In some embodiments, c_(A), c_(B),        and c_(M) are each independently a 0-1 amino acid. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from any amino acid having a free thiol group, any        amino acid having a N-terminal amine group, and any amino acid        with a side chain capable of forming an oxime or hydrazone bond        upon reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1).

Disclosed herein, in certain embodiments, are methods of delivering atherapeutic agent to a tissue of interest, comprising contacting thetissue of interest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 5 consecutive        glutamates (SEQ ID NO: 5);    -   B is a peptide with a sequence comprising 8 consecutive        arginines (SEQ ID NO: 6);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   at least one of D_(A) and D_(B) is independently a therapeutic        agent; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, X comprises        the amino acid sequence RPLALWRS (SEQ ID NO: 7).

Disclosed herein, in certain embodiments, are methods of delivering atherapeutic agent to a tissue of interest, comprising contacting thetissue of interest with a molecule of Formula I:

[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I

wherein,

-   -   X is a peptide linker cleavable by a matrix metalloproteinase;    -   A is a peptide with a sequence comprising 9 consecutive        glutamates (SEQ ID NO: 13);    -   B is a peptide with a sequence comprising 9 consecutive        arginines (SEQ ID NO: 14);    -   c_(A), c_(B), and c_(M) each independently comprise 0-1 amino        acid;    -   M is a polyethylene glycol (PEG) polymer; and    -   at least one of D_(A) and D_(B) is independently a therapeutic        agent; and        wherein [c_(M)-M] is bound to at any position on A or X,        [D_(A)-c_(A)] is bound to any amino acid on A, and [c_(B)-D_(B)]        is bound to any amino acid on B.        In some embodiments, c_(A), c_(B), and c_(M) are each        independently a 0-1 amino acid. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from any amino        acid having a free thiol group, any amino acid having a        N-terminal amine group, and any amino acid with a side chain        capable of forming an oxime or hydrazone bond upon reaction with        a hydroxylamine or hydrazine group. In some embodiments, c_(A),        c_(B), and c_(M) are each independently selected from        D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(M) is any amino acid with a        side chain capable of forming an oxime or hydrazone bond upon        reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(M) is para-4-acetyl L-phenylalanine. In some        embodiments, X comprises the amino acid sequence PLGLAG (SEQ ID        NO: 2). In some embodiments, X comprises the amino acid sequence        PLG-C(me)-AG (SEQ ID NO: 1). In some embodiments, X comprises        the amino acid sequence RPLALWRS (SEQ ID NO: 7).

In some embodiments, targeted delivery of a therapeutic agent to a cellor tissue enables a medical professional to treat a specific tissue(e.g., cancerous tissue). In some embodiments, targeted delivery of atherapeutic agent to a cell or tissue decreases the dosage of thetherapeutic agent. In some embodiments, targeted delivery of atherapeutic agent to a cell or tissue decreases contact of thetheraperutic agent with healthy tissue. In some embodiments, targeteddelivery of a therapeutic agent to a cell or tissue decreases unwantedside-effects arising from use of high concentrations of a therapeuticagent or contact. In some embodiments, targeted delivery of atherapeutic agent to a cell or tissue decreases unwanted side-effectsarising from contact between the therapeutic agent and healthy tissue.

Therapeutic Agents

In some embodiments, a therapeutic agent is selected from: achemotherapeutic agent, a steroid, an immunotherapeutic agent, atargeted therapy, an anti-inflammatory agent, or a combination thereof.

In some embodiments, a therapeutic agent is a B cell receptor pathwayinhibitor. In some embodiments, a therapeutic agent is a CD79Ainhibitor, a CD79B inhibitor, a CD19 inhibitor, a Lyn inhibitor, a Sykinhibitor, a PI3K inhibitor, a Blnk inhibitor, a PLCγ inhibitor, a PKCβinhibitor, or a combination thereof. In some embodiments, a therapeuticagent is an antibody, B cell receptor signaling inhibitor, a PI3Kinhibitor, an IAP inhibitor, an mTOR inhibitor, aradioimmunotherapeutic, a DNA damaging agent, a proteosome inhibitor, ahistone deacytlase inhibitor, a protein kinase inhibitor, a hedgehoginhibitor, an Hsp90 inhibitor, a telomerase inhibitor, a Jak1/2inhibitor, a protease inhibitor, a PKC inhibitor, a PARP inhibitor, or acombination thereof. In some embodiments, a therapeutic agent isselected from: chlorambucil, ifosphamide, doxorubicin, mesalazine,thalidomide, lenalidomide, temsirolimus, everolimus, fludarabine,fostamatinib, paclitaxel, docetaxel, ofatumumab, rituximab,dexamethasone, prednisone, CAL-101, ibritumomab, tositumomab,bortezomib, pentostatin, endostatin, bendamustine, chlorambucil,chlormethine, cyclophosphamide, ifosfamide, melphalan, prednimustine,trofosfamide, busulfan, mannosulfan, treosulfan, carboquone, thiotepa,triaziquone, carmustine, fotemustine, lomustine, nimustine, ranimustine,semustine, streptozocin, etoglucid, dacarbazine, mitobronitol,pipobroman, temozolomide, methotrexate, permetrexed, pralatrexate,raltitrexed, cladribine, clofarabine, fludarabine, mercaptopurine,nelarabine, tioguanine, azacitidine, capecitabine, carmofur, cytarabine,decitabine, fluorouracil, gemcitabine, tegafur, vinblastine,vincristine, vindesine, vinflunine, vinorelbine, etoposide, teniposide,demecolcine, docetaxel, paclitaxel, paclitaxel poliglumex, trabectedin,dactinomycin, aclarubicin, daunorubicin, doxorubicin, epirubicin,idarubicin, mitoxantrone, pirarubicin, valrubicin, zorubincin,bleomycin, ixabepilone, mitomycin, plicamycin, carboplatin, cisplatin,oxaliplatin, satraplatin, procarbazine, aminolevulinic acid,efaproxiral, methyl aminolevulinate, porfimer sodium, temoporfin,dasatinib, erlotinib, everolimus, gefitinib, imatinib, lapatinib,nilotinib, pazonanib, sorafenib, sunitinib, temsirolimus, alitretinoin,altretamine, amzacrine, anagrelide, arsenic trioxide, asparaginase,bexarotene, bortezomib, celecoxib, denileukin diftitox, estramustine,hydroxycarbamide, irinotecan, lonidamine, masoprocol, miltefosein,mitoguazone, mitotane, oblimersen, pegaspargase, pentostatin,romidepsin, sitimagene ceradenovec, tiazofurine, topotecan, tretinoin,vorinostat, diethylstilbenol, ethinylestradiol, fosfestrol,polyestradiol phosphate, gestonorone, medroxyprogesterone, megestrol,buserelin, goserelin, leuprorelin, triptorelin, fulvestrant, tamoxifen,toremifene, bicalutamide, flutamide, nilutamide, aminoglutethimide,anastrozole, exemestane, formestane, letrozole, vorozole, abarelix,degarelix, histamine dihydrochloride, mifamurtide, pidotimod,plerixafor, roquinimex, thymopentin, everolimus, gusperimus,leflunomide, mycophenolic acid, sirolimus, ciclosporin, tacrolimus,azathioprine, lenalidomide, methotrexate, thalidomide, iobenguane,ancestim, filgrastim, lenograstim, molgramostim, pegfilgrastim,sargramostim, interferon alfa natural, interferon alfa-2a, interferonalfa-2b, interferon alfacon-1, interferon alfa-nl, interferon betanatural, interferon beta-1a, interferon beta-1b, interferon gamma,peginterferon alfa-2a, peginterferon alfa-2b, aldesleukin, oprelvekin,BCG vaccine, glatiramer acetate, histamine dihydrochloride,immunocyanin, lentinan, melanoma vaccine, mifamurtide, pegademase,pidotimod, plerixafor, poly I:C, poly ICLC, roquinimex, tasonermin,thymopentin, abatacept, abetimus, alefacept, antilymphocyteimmunoglobulin (horse), antithymocyte immunoglobulin (rabbit),eculizumab, efalizumab, everolimus, gusperimus, leflunomide,muromab-CD3, mycophenolic acid, natalizumab, sirolimus, adalimumab,afelimomab, certolizumab pegol, etanercept, golimumab, infliximab,anakinra, basiliximab, canakinumab, daclizumab, mepolizumab, rilonacept,tocilizumab, ustekinumab, ciclosporin, tacrolimus, azathioprine,lenalidomide, methotrexate, thalidomide, adalimumab, alemtuzumab,bevacizumab, cetuximab, certolizumab pegol, eculizumab, efalizumab,gemtuzumab, ibritumomab tiuxetan, muromonab-CD3, natalizumab,panitumumab, ranibizumab, rituximab, tositumomab, trastuzumab,catumaxomab, edrecolomab, ofatumumab, muromab-CD3, afelimomab,golimumab, ibritumomab tiuxetan, abagovomab, adecatumumab, alemtuzumab,anti-CD30 monoclonal antibody Xmab2513, anti-MET monoclonal antibodyMetMab, apolizumab, apomab, arcitumomab, bispecific antibody 2B1,blinatumomab, brentuximab vedotin, capromab pendetide, cixutumumab,claudiximab, conatumumab, dacetuzumab, denosumab, eculizumab,epratuzumab, epratuzumab, ertumaxomab, etaracizumab, figitumumab,fresolimumab, galiximab, ganitumab, gemtuzumab ozogamicin,glembatumumab, ibritumomab, inotuzumab ozogamicin, ipilimumab,lexatumumab, lintuzumab, lintuzumab, lucatumumab, mapatumumab,matuzumab, milatuzumab, monoclonal antibody CC49, necitumumab,nimotuzumab, ofatumumab, oregovomab, pertuzumab, ramacurimab,ranibizumab, siplizumab, sonepcizumab, tanezumab, tositumomab,trastuzumab, tremelimumab, tucotuzumab celmoleukin, veltuzumab,visilizumab, volociximab, zalutumumab, a syk inhibitor (e.g., R788),enzastaurin, dasatinib, erlotinib, everolimus, gefitinib, imatinib,lapatinib, nilotinib, pazonanib, sorafenib, sunitinib, temsirolimus, anangiogenesis inhibitor (e.g., GT-111, JI-101, R1530), a kinaseinhibitors (e.g., AC220, AC480, ACE-041, AMG 900, AP24534, Arry-614,AT7519, AT9283, AV-951, axitinib, AZD1152, AZD7762, AZD8055, AZD8931,bafetinib, BAY 73-4506, BGJ398, BGT226, BI 811283, B16727, BIM 1120,BIBW 2992, BMS-690154, BMS-777607, BMS-863233, BSK-461364, CAL-101,CEP-11981, CYC116, DCC-2036, dinaciclib, dovitinib lactate, E7050, EMD1214063, ENMD-2076, fostamatinib disodium, GSK2256098, GSK690693,INCB18424, INNO-406, JNJ-26483327, JX-594, KX2-391, linifanib,LY2603618, MGCD265, MK-0457, MK1496, MLN8054, MLN8237, MP470,NMS-1116354, NMS-1286937, ON 01919.Na, OSI-027, OSI-930, Btk inhibitor,PF-00562271, PF-02341066, PF-03814735, PF-04217903, PF-04554878,PF-04691502, PF-3758309, PHA-739358, PLC3397, progenipoietin, R547,R763, ramucirumab, regorafenib, R05185426, SAR103168, S3333333CH 727965,SGI-1176, SGX523, SNS-314, TAK-593, TAK-901, TKI258, TLN-232, TTP607,XL147, XL228, XL281R05126766, XL418, XL765), an inhibitor ofmitogen-activated protein kinase signaling (e.g., U0126, PD98059,PD184352, PD0325901, ARRY-142886, SB239063, SP600125, BAY 43-9006,wortmannin, or LY294002), adriamycin, dactinomycin, bleomycin,vinblastine, cisplatin, acivicin, aclarubicin, acodazole hydrochloride,acronine, adozelesin, aldesleukin, altretamine, ambomycin, ametantroneacetate, aminoglutethimide, amsacrine, anastrozole, anthramycin,asparaginase, asperlin, azacitidine, azetepa, azotomycin, batimastat,benzodepa, bicalutamide, bisantrene hydrochloride, bisnafide dimesylate,bizelesin, bleomycin sulfate, brequinar sodium, bropirimine, busulfan,cactinomycin, calusterone, caracemide, carbetimer, carboplatin,carmustine, carubicin hydrochloride, carzelesin, cedefingol,chlorambucil, cirolemycin, cladribine, crisnatol mesylate,cyclophosphamide, cytarabine, dacarbazine, daunorubicin hydrochloride,decitabine, dexormaplatin, dezaguanine, dezaguanine mesylate,diaziquone, doxorubicin, doxorubicin hydrochloride, droloxifene,droloxifene citrate, dromostanolone propionate, duazomycin, edatrexate,eflornithine hydrochloride, elsamitrucin, enloplatin, enpromate,epipropidine, epirubicin hydrochloride, erbulozole, esorubicinhydrochloride, estramustine, estramustine phosphate sodium, etanidazole,etoposide, etoposide phosphate, etoprine, fadrozole hydrochloride,fazarabine, fenretinide, floxuridine, fludarabine phosphate,fluorouracil, flurocitabine, fosquidone, fostriecin sodium, gemcitabine,gemcitabine hydrochloride, hydroxyurea, idarubicin hydrochloride,ifosfamide, iimofosine, interleukin Il (including recombinantinterleukin II, or rlL2), interferon alfa-2a, interferon alfa-2b,interferon alfa-nl, interferon alfa-n3, interferon beta-1 a, interferongamma-1 b, iproplatin, irinotecan hydrochloride, lanreotide acetate,letrozole, leuprolide acetate, liarozole hydrochloride, lometrexolsodium, lomustine, losoxantrone hydrochloride, masoprocol, maytansine,mechlorethamine hydrochloride, megestrol acetate, melengestrol acetate,melphalan, menogaril, mercaptopurine, methotrexate, methotrexate sodium,metoprine, meturedepa, mitindomide, mitocarcin, mitocromin, mitogillin,mitomalcin, mitomycin, mitosper, mitotane, mitoxantrone hydrochloride,mycophenolic acid, nocodazoie, nogalamycin, ormaplatin, oxisuran,pegaspargase, peliomycin, pentamustine, peplomycin sulfate,perfosfamide, pipobroman, piposulfan, piroxantrone hydrochloride,plicamycin, plomestane, porfimer sodium, porfiromycin, prednimustine,procarbazine hydrochloride, puromycin, puromycin hydrochloride,pyrazofurin, riboprine, rogletimide, safingol, safingol hydrochloride,semustine, simtrazene, sparfosate sodium, sparsomycin, spirogermaniumhydrochloride, spiromustine, spiroplatin, streptonigrin, streptozocin,sulofenur, talisomycin, tecogalan sodium, tegafur, teloxantronehydrochloride, temoporfin, teniposide, teroxirone, testolactone,thiamiprine, thioguanine, thiotepa, tiazofurin, tirapazamine, toremifenecitrate, trestolone acetate, triciribine phosphate, trimetrexate,trimetrexate glucuronate, triptorelin, tubulozole hydrochloride, uracilmustard, uredepa, vapreotide, verteporfin, vinblastine sulfate,vincristine sulfate, vindesine, vindesine sulfate, vinepidine sulfate,vinglycinate sulfate, vinleurosine sulfate, vinorelbine tartrate,vinrosidine sulfate, vinzolidine sulfate, vorozole, zeniplatin,zinostatin, zorubicin hydrochloride. In some embodiments, a therapeuticagent is selected from: 20-epi-1, 25 dihydroxyvitamin D3,5-ethynyluracil, abiraterone, aclarubicin, acylfulvene, adecypenol,adozelesin, aldesleukin, ALL-TK antagonists, altretamine, ambamustine,amidox, amifostine, aminolevulinic acid, amrubicin, amsacrine,anagrelide, anastrozole, andrographolide, angiogenesis inhibitors,antagonist D, antagonist G, antarelix, anti-dorsalizing morphogeneticprotein-1, antiandrogen, prostatic carcinoma, antiestrogen,antineoplaston, antisense oligonucleotides, aphidicolin glycinate,apoptosis gene modulators, apoptosis regulators, apurinic acid,ara-CDP-DL-PTBA, arginine deaminase, asulacrine, atamestane,atrimustine, axinastatin 1, axinastatin 2, axinastatin 3, azasetron,azatoxin, azatyrosine, baccatin III derivatives, balanol, batimastat,BCR/ABL antagonists, benzochlorins, benzoylstaurosporine, beta lactamderivatives, beta-alethine, betaclamycin B, betulinic acid, bFGFinhibitor, bicalutamide, bisantrene, bisaziridinylspermine, bisnafide,bistratene A, bizelesin, breflate, bropirimine, budotitane, buthioninesulfoximine, calcipotriol, calphostin C, camptothecin derivatives,canarypox IL-2, capecitabine, carboxamide-amino-triazole,carboxyamidotriazole, CaRest M3, CARN 700, cartilage derived inhibitor,carzelesin, casein kinase inhibitors (ICOS), castanospermine, cecropinB, cetrorelix, chlorins, chloroquinoxaline sulfonamide, cicaprost,cis-porphyrin, cladribine, clomifene analogues, clotrimazole,collismycin A, collismycin B, combretastatin A4, combretastatinanalogue, conagenin, crambescidin 816, crisnatol, cryptophycin 8,cryptophycin A derivatives, curacin A, cyclopentanthraquinones,cycloplatam, cypemycin, cytarabine ocfosfate, cytolytic factor,cytostatin, dacliximab, decitabine, dehydrodidemnin B, deslorelin,dexamethasone, dexifosfamide, dexrazoxane, dexverapamil, diaziquone,didemnin B, didox, diethylnorspermine, dihydro-5-azacytidine,9-dioxamycin, diphenyl spiromustine, docosanol, dolasetron,doxifluridine, droloxifene, dronabinol, duocarmycin SA, ebselen,ecomustine, edelfosine, edrecolomab, eflornithine, elemene, emitefur,epirubicin, epristeride, estramustine analogue, estrogen agonists,estrogen antagonists, etanidazole, etoposide phosphate, exemestane,fadrozole, fazarabine, fenretinide, filgrastim, finasteride,flavopiridol, flezelastine, fluasterone, fludarabine, fluorodaunorunicinhydrochloride, forfenimex, formestane, fostriecin, fotemustine,gadolinium texaphyrin, gallium nitrate, galocitabine, ganirelix,gelatinase inhibitors, gemcitabine, glutathione inhibitors, hepsulfam,heregulin, hexamethylene bisacetamide, hypericin, ibandronic acid,idarubicin, idoxifene, idramantone, ilmofosine, ilomastat,imidazoacridones, imiquimod, immunostimulant peptides, insulin-such asfor example growth factor-1 receptor inhibitor, interferon agonists,interferons, interleukins, iobenguane, iododoxorubicin, ipomeanol, 4-,iroplact, irsogladine, isobengazole, isohomohalicondrin B, itasetron,jasplakinolide, kahalalide F, lamellarin-N triacetate, lanreotide,leinamycin, lenograstim, lentinan sulfate, leptolstatin, letrozole,leukemia inhibiting factor, leukocyte alpha interferon,leuprolide+estrogen+progesterone, leuprorelin, levamisole, liarozole,linear polyamine analogue, lipophilic disaccharide peptide, lipophilicplatinum compounds, lissoclinamide 7, lobaplatin, lombricine,lometrexol, lonidamine, losoxantrone, lovastatin, loxoribine,lurtotecan, lutetium texaphyrin, lysofylline, lytic peptides,maitansine, mannostatin A, marimastat, masoprocol, maspin, matrilysininhibitors, matrix metalloproteinase inhibitors, menogaril, merbarone,meterelin, methioninase, metoclopramide, MIF inhibitor, mifepristone,miltefosine, mirimostim, mismatched double stranded RNA, mitoguazone,mitolactol, mitomycin analogues, mitonafide, mitotoxin fibroblast growthfactor-saporin, mitoxantrone, mofarotene, molgramostim, monoclonalantibody, human chorionic gonadotrophin, monophosphoryl lipidA+myobacterium cell wall sk, mopidamol, multiple drug resistance geneinhibitor, multiple tumor suppressor 1-based therapy, mustard anticanceragent, mycaperoxide B, mycobacterial cell wall extract, myriaporone,N-acetyldinaline, N-substituted benzamides, nafarelin, nagrestip,naloxone+pentazocine, napavin, naphterpin, nartograstim, nedaplatin,nemorubicin, neridronic acid, neutral endopeptidase, nilutamide,nisamycin, nitric oxide modulators, nitroxide antioxidant, nitrullyn,O6-benzylguanine, octreotide, okicenone, oligonucleotides, onapristone,ondansetron, ondansetron, oracin, oral cytokine inducer, ormaplatin,osaterone, oxaliplatin, oxaunomycin, palauamine, palmitoylrhizoxin,pamidronic acid, panaxytriol, panomifene, parabactin, pazelliptine,pegaspargase, peldesine, pentosan polysulfate sodium, pentostatin,pentrozole, perflubron, perfosfamide, perillyl alcohol, phenazinomycin,phenylacetate, phosphatase inhibitors, picibanil, pilocarpinehydrochloride, pirarubicin, piritrexim, placetin A, placetin B,plasminogen activator inhibitor, platinum complex, platinum compounds,platinum-triamine complex, porfimer sodium, porfiromycin, prednisone,propyl bis-acridone, prostaglandin J2, proteasome inhibitors, proteinA-based immune modulator, protein kinase C inhibitor, protein kinase Cinhibitors, microalgal, protein tyrosine phosphatase inhibitors, purinenucleoside phosphorylase inhibitors, purpurins, pyrazoloacridine,pyridoxylated hemoglobin polyoxyethylerie conjugate, raf antagonists,raltitrexed, ramosetron, ras farnesyl protein transferase inhibitors,ras inhibitors, ras-GAP inhibitor, retelliptine demethylated, rhenium Re186 etidronate, rhizoxin, ribozymes, RII retinamide, rogletimide,rohitukine, romurtide, roquinimex, rubiginone B 1, ruboxyl, safingol,saintopin, SarCNU, sarcophytol A, sargramostim, Sdi 1 mimetics,semustine, senescence derived inhibitor 1, sense oligonucleotides,signal transduction inhibitors, signal transduction modulators, singlechain antigen-binding protein, sizofiran, sobuzoxane, sodiumborocaptate, sodium phenylacetate, solverol, somatomedin bindingprotein, sonermin, sparfosic acid, spicamycin D, spiromustine,splenopentin, spongistatin 1, squalamine, stem cell inhibitor, stem-celldivision inhibitors, stipiamide, stromelysin inhibitors, sulfinosine,superactive vasoactive intestinal peptide antagonist, suradista,suramin, swainsonine, synthetic glycosaminoglycans, tallimustine,tamoxifen methiodide, tauromustine, tazarotene, tecogalan sodium,tegafur, tellurapyrylium, telomerase inhibitors, temoporfin,temozolomide, teniposide, tetrachlorodecaoxide, tetrazomine,thaliblastine, thiocoraline, thrombopoietin, thrombopoietin mimetic,thymalfasin, thymopoietin receptor agonist, thymotrinan, thyroidstimulating hormone, tin ethyl etiopurpurin, tirapazamine, titanocenebichloride, topsentin, toremifene, totipotent stem cell factor,translation inhibitors, tretinoin, triacetyluridine, triciribine,trimetrexate, triptorelin, tropisetron, turosteride, tyrosine kinaseinhibitors, tyrphostins, UBC inhibitors, ubenimex, urogenitalsinus-derived growth inhibitory factor, urokinase receptor antagonists,vapreotide, variolin B, vector system, erythrocyte gene therapy,velaresol, veramine, verdins, verteporfin, vinorelbine, vinxaltine,vitaxin, vorozole, zanoterone, zeniplatin, zilascorb, zinostatinstimalamer, mechloroethamine, cyclophosphamide, chlorambucil, busulfan,carmustine, lomusitne, decarbazine, methotrexate, cytarabine,mercaptopurine, thioguanine, pentostatin, mechloroethamine,cyclophosphamide, chlorambucil, meiphalan, ethylenimine, methylmelamine,hexamethlymelamine, thiotepa, busulfan, carmustine, lomusitne,semustine, streptozocin, decarbazine, fluorouracil, floxouridine,cytarabine, mercaptopurine, thioguanine, pentostatin, erbulozole (alsoknown as R-55104), Dolastatin 10 (also known as DLS-10 and NSC-376128),Mivobulin isethionate (also known as CI-980), Vincristine, NSC-639829,Discodermolide (also known as NVP-XX-A-296), ABT-751 (Abbott, also knownas E-7010), Altorhyrtins (such as Altorhyrtin A and Altorhyrtin C),Spongistatins (such as Spongistatin 1, Spongistatin 2, Spongistatin 3,Spongistatin 4, Spongistatin 5, Spongistatin 6, Spongistatin 7,Spongistatin 8, and Spongistatin 9), Cemadotin hydrochloride (also knownas LU-103793 and NSC-D-669356), Epothilones (such as Epothilone A,Epothilone B, Epothilone C (also known as desoxyepothilone A or dEpoA),Epothilone D (also referred to as KOS-862, dEpoB, and desoxyepothiloneB), Epothilone E, Epothilone F, Epothilone B N-oxide, Epothilone AN-oxide, 16-aza-epothilone B, 21-aminoepothilone B (also known asBMS-310705), 21-hydroxyepothilone D (also known as Desoxyepothilone Fand dEpoF), 26-fluoroepothilone), Auristatin PE (also known asNSC-654663), Soblidotin (also known as TZT-1027), LS-4559-P (Pharmacia,also known as LS-4577), LS-4578 (Pharmacia, also known as LS-477-P),LS-4477 (Pharmacia), LS-4559 (Pharmacia), RPR-112378 (Aventis),Vincristine sulfate, DZ-3358 (Daiichi), FR-182877 (Fujisawa, also knownas WS-9885B), GS-164 (Takeda), GS-198 (Takeda), KAR-2 (Hungarian Academyof Sciences), BSF-223651 (BASF, also known as ILX-651 and LU-223651),SAH-49960 (Lilly/Novartis), SDZ-268970 (Lilly/Novartis), AM-97(Armad/Kyowa Hakko), AM-132 (Armad), AM-138 (Armad/Kyowa Hakko),IDN-5005 (Indena), Cryptophycin 52 (also known as LY-355703), AC-7739(Ajinomoto, also known as AVE-8063A and CS-39.HCI), AC-7700 (Ajinomoto,also known as AVE-8062, AVE-8062A, CS-39-L-Ser.HCI, and RPR-258062A),Vitilevuamide, Tubulysin A, Canadensol, Centaureidin (also known asNSC-106969), T-138067 (Tularik, also known as T-67, TL-138067 andTI-138067), COBRA-1 (Parker Hughes Institute, also known as DDE-261 andWHI-261), H10 (Kansas State University), H16 (Kansas State University),Oncocidin A1 (also known as BTO-956 and DIME), DDE-313 (Parker HughesInstitute), Fijianolide B, Laulimalide, SPA-2 (Parker Hughes Institute),SPA-1 (Parker Hughes Institute, also known as SPIKET-P), 3-IAABU(Cytoskeleton/Mt. Sinai School of Medicine, also known as MF-569),Narcosine (also known as NSC-5366), Nascapine, D-24851 (Asta Medica),A-105972 (Abbott), Hemiasterlin, 3-BAABU (Cytoskeleton/Mt. Sinai Schoolof Medicine, also known as MF-191), TMPN (Arizona State University),Vanadocene acetylacetonate, T-138026 (Tularik), Monsatrol, lnanocine(also known as NSC-698666), 3-1AABE (Cytoskeleton/Mt. Sinai School ofMedicine), A-204197 (Abbott), T-607 (Tuiarik, also known as T-900607),RPR-115781 (Aventis), Eleutherobins (such as Desmethyleleutherobin,Desaetyleleutherobin, lsoeleutherobin A, and Z-Eleutherobin),Caribaeoside, Caribaeolin, Halichondrin B, D-64131 (Asta Medica),D-68144 (Asta Medica), Diazonamide A, A-293620 (Abbott), NPI-2350(Nereus), Taccalonolide A, TUB-245 (Aventis), A-259754 (Abbott),Diozostatin, (−)-Phenylahistin (also known as NSCL-96F037), D-68838(Asta Medica), D-68836 (Asta Medica), Myoseverin B, D-43411 (Zentaris,also known as D-81862), A-289099 (Abbott), A-318315 (Abbott), HTI-286(also known as SPA-110, trifluoroacetate salt) (Wyeth), D-82317(Zentaris), D-82318 (Zentaris), SC-12983 (NCI), Resverastatin phosphatesodium, BPR-OY-007 (National Health Research Institutes), and SSR-250411(Sanofi).

In some embodiments, a therapeutic agent is an anti-inflammatory agent.In some embodiments, a therapeutic agent is an anti-TNF agent, an IL-1receptor antagonist, an IL-2 receptor antagonist, a cytotoxic agent, animmunomodulatory agent, an antibiotic, a T-cell co-stimulatory blocker,a B cell depleting agent, an immunosuppressive agent, an alkylatingagent, an anti-metabolite, a plant alkaloid, a terpenoids, atopoisomerase inhibitor, an antitumour antibiotic, an antibody, ahormonal therapy, an anti-diabetes agent, a leukotriene inhibitor, orcombinations thereof. In some embodiments, a therapeutic agent isselected from: alefacept, efalizumab, methotrexate, acitretin,isotretinoin, hydroxyurea, mycophenolate mofetil, sulfasalazine,6-Thioguanine, Dovonex, Taclonex, betamethasone, tazarotene,hydroxychloroquine, etanercept, adalimumab, infliximab, abatacept,rituximab, tratuzumab, Anti-CD45 monoclonal antibody AHN-12 (NCI),Iodine-131 Anti-B1 Antibody (Corixa Corp.), anti-CD66 monoclonalantibody BW 250/183 (NCI, Southampton General Hospital), anti-CD45monoclonal antibody (NCI, Baylor College of Medicine), antibodyanti-anb3 integrin (NCI), BIW-8962 (BioWa Inc.), Antibody BC8 (NCI),antibody muJ591 (NCI), indium In 111 monoclonal antibody MN-14 (NCI),yttrium Y 90 monoclonal antibody MN-14 (NCI), F105 Monoclonal Antibody(NIAID), Monoclonal Antibody RAV12 (Raven Biotechnologies), CAT-192(Human Anti-TGF-Beta1 Monoclonal Antibody, Genzyme), antibody 3F8 (NCI),177Lu-J591 (Weill Medical College of Cornell University), TB-403(BioInvent International AB), anakinra, azathioprine, cyclophosphamide,cyclosporine A, leflunomide, d-penicillamine, amitriptyline, ornortriptyline, chlorambucil, nitrogen mustard, prasterone, LJP 394(abetimus sodium), LJP 1082 (La Jolla Pharmaceutical), eculizumab,belibumab, rhuCD40L (NIAID), epratuzumab, sirolimus, tacrolimus,pimecrolimus, thalidomide, antithymocyte globulin-equine (Atgam,Pharmacia Upjohn), antithymocyte globulin-rabbit (Thymoglobulin,Genzyme), Muromonab-CD3 (FDA Office of Orphan Products Development),basiliximab, daclizumab, riluzole, cladribine, natalizumab, interferonbeta-1b, interferon beta-1a, tizanidine, baclofen, mesalazine, asacol,pentasa, mesalamine, balsalazide, olsalazine, 6-mercaptopurine, AIN457(Anti IL-17 Monoclonal Antibody, Novartis), theophylline, D2E7 (a humananti-TNF mAb from Knoll Pharmaceuticals), Mepolizumab (Anti-IL-5antibody, SB 240563), Canakinumab (Anti-IL-1 Beta Antibody, NIAMS),Anti-IL-2 Receptor Antibody (Daclizumab, NHLBI), CNTO 328 (Anti IL-6Monoclonal Antibody, Centocor), ACZ885 (fully humananti-interleukin-1beta monoclonal antibody, Novartis), CNTO 1275 (FullyHuman Anti-IL-12 Monoclonal Antibody, Centocor),(3S)—N-hydroxy-4-({4-[(4-hydroxy-2-butynyl)oxy]phenyl}sulfonyl)-2,2-dimet-hyl-3-thiomorpholinecarboxamide (apratastat), golimumab (CNTO 148), Onercept, BG9924 (BiogenIdec), Certolizumab Pegol (CDP870, UCB Pharma), AZD9056 (AstraZeneca),AZD5069 (AstraZeneca), AZD9668 (AstraZeneca), AZD7928 (AstraZeneca),AZD2914 (AstraZeneca), AZD6067 (AstraZeneca), AZD3342 (AstraZeneca),AZD8309 (AstraZeneca),[(1R)-3-methyl-1-({(2S)-3-phenyl-2-[(pyrazin-2-ylcarbonyl)amino]propanoyl}amino)butyl]boronicacid (Bortezomib), AMG-714, (Anti-IL 15 Human Monoclonal Antibody,Amgen), ABT-874 (Anti IL-12 monoclonal antibody, Abbott Labs), MRA(Tocilizumab, an Anti IL-6 Receptor Monoclonal Antibody, ChugaiPharmaceutical), CAT-354 (a human anti-interleukin-13 monoclonalantibody, Cambridge Antibody Technology, MedImmune), aspirin, salicylicacid, gentisic acid, choline magnesium salicylate, choline salicylate,choline magnesium salicylate, choline salicylate, magnesium salicylate,sodium salicylate, diflunisal, carprofen, fenoprofen, fenoprofencalcium, flurobiprofen, ibuprofen, ketoprofen, nabutone, ketolorac,ketorolac tromethamine, naproxen, oxaprozin, diclofenac, etodolac,indomethacin, sulindac, tolmetin, meclofenamate, meclofenamate sodium,mefenamic acid, piroxicam, meloxicam, celecoxib, rofecoxib, valdecoxib,parecoxib, etoricoxib, lumiracoxib, CS-502 (Sankyo), JTE-522 (JapanTobacco Inc.), L-745,337 (Almirall), NS398 (Sigma), betamethasone(Celestone), prednisone (Deltasone), alclometasone, aldosterone,amcinonide, beclometasone, betamethasone, budesonide, ciclesonide,clobetasol, clobetasone, clocortolone, cloprednol, cortisone,cortivazol, deflazacort, deoxycorticosterone, desonide, desoximetasone,desoxycortone, dexamethasone, diflorasone, diflucortolone,difluprednate, fluclorolone, fludrocortisone, fludroxycortide,flumetasone, flunisolide, fluocinolone acetonide, fluocinonide,fluocortin, fluocortolone, fluorometholone, fluperolone, fluprednidene,fluticasone, formocortal, formoterol, halcinonide, halometasone,hydrocortisone, hydrocortisone aceponate, hydrocortisone buteprate,hydrocortisone butyrate, loteprednol, medrysone, meprednisone,methylprednisolone, methylprednisolone aceponate, mometasone furoate,paramethasone, prednicarbate, prednisone, rimexolone, tixocortol,triamcinolone, ulobetasol, Pioglitazone, Rosiglitazone, Glimepiride,Glyburide, Chlorpropamide, Glipizide, Tolbutamide, Tolazamide,Glucophage, Metformin, (glyburide+metformin), Rosiglitazone+metformin,(Rosiglitazone+glimepiride), Exenatide, Insulin, Sitagliptin, (glipizideand metformin), Repaglinide, Acarbose, Nateglinide, Orlistat, cisplatin;carboplatin; oxaliplatin; mechlorethamine; cyclophosphamide;chlorambucil; vincristine; vinblastine; vinorelbine; vindesine;mercaptopurine; fludarabine; pentostatin; cladribine; 5-fluorouracil(5FU); floxuridine (FUDR); cytosine arabinoside; trimethoprim;pyrimethamine; pemetrexed; paclitaxel; docetaxel; etoposide; teniposide;irinotecan; topotecan; amsacrine; etoposide; etoposide phosphate;teniposide; dactinomycin; doxorubicin; daunorubicin; valrubicine;idarubicine; epirubicin; bleomycin; plicamycin; mitomycin; finasteride;goserelin; aminoglutethimide; anastrozole; letrozole; vorozole;exemestane; 4-androstene-3,6,17-trione (“6-OXO”;1,4,6-androstatrien-3,17-dione (ATD); formestane; testolactone;fadrozole; A-81834(3-(3-(1,1-dimethylethylthio-5-(quinoline-2-ylmethoxy)-1-(4-chloromethylphenyl)indole-2-yl)-2,2-dimethylpropionaldehydeoxime-O-2-acetic acid; AME103 (Amira); AME803 (Amira); atreleuton;BAY-x-1005((R)-(+)-alpha-cyclopentyl-4-(2-quinolinylmethoxy)-Benzeneacetic acid);CJ-13610(4-(3-(4-(2-Methyl-imidazol-1-yl)-phenylsulfanyl)-phenyl)-tetrahydro-pyran-4-carboxylicacid amide); DG-031 (DeCode); DG-051 (DeCode); MK886(1-[(4-chlorophenyl)methyl]3-[(1,1-dimethylethyl)thio]-α,α-dimethyl-5-(1-methylethyl)-1H-indole-2-propanoicacid, sodium salt); MK591(3-(1-4[(4-chlorophenyl)methyl]-3-[(t-butylthio)-5-((2-quinoly)methoxy)-1H-indole-2]-,dimehtylpropanoic acid); RP64966([4-[5-(3-Phenyl-propyl)thiophen-2-yl]butoxy] acetic acid); SA6541((R)—S-[[4-(dimethylamino)phenyl]methyl]-N-(3-mercapto-2methyl-1-oxopropyl-L-cycteine);SC-56938 (ethyl-1-[2-[4-(phenylmethyl)phenoxy]ethyl]-4-piperidine-carboxylate); VIA-2291 (Via Pharmaceuticals);WY-47,288 (2-[(1-naphthalenyloxy)methyl]quinoline); zileuton; ZD-2138(6-((3-fluoro-5-(tetrahydro-4-methoxy-2H-pyran-4yl)phenoxy)methyl)-1-methyl-2(1H)-quinlolinone);doxycycline; or combinations thereof.

Starting Materials

Disclosed herein, in certain embodiments, are molecules of Formula II,having the structure:

A₁-X₁-B₁;   Formula II

wherein,

-   -   X₁ is a cleavable linker;    -   A₁ is a peptide with a sequence comprising 5 to 9 acidic amino        acids and having a first reactive amino acid moiety c_(A);    -   B₁ is a peptide with a sequence comprising 7 to 9 basic amino        acids and having a second reactive amino acid moiety c_(B); and    -   A₁-X₁-B₁ has a third reactive amino acid moiety c_(M) on A₁ or        X₁; and        wherein c_(A) is capable of reacting with a first cargo moiety        comprising D_(A), c_(B) is capable of reacting with a second        cargo moiety comprising D_(B), and c_(M) is capable of reacting        with a macromolecular carrier comprising M to form a molecule of        Formula I.        In some embodiments, the c_(A), c_(B), and c_(M) have functional        groups that are orthogonally reactive. In some embodiments,        c_(A), c_(B), and c_(M) are each independently selected from a        naturally-occurring amino acid or a non-naturally-occurring        amino acid. In some embodiments, c_(A), c_(B), and c_(M) are        each independently selected from a D amino acid, a L amino acid,        an α-amino acid, a β-amino acid, or a γ-amino acid. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from any amino acid having a free thiol group, any        amino acid having a N-terminal amine group, and any amino acid        with a side chain capable of forming an oxime or hydrazone bond        upon reaction with a hydroxylamine or hydrazine group. In some        embodiments, c_(A), c_(B), and c_(M) are each independently        selected from D-cysteine, D-glutamate, lysine, and para-4-acetyl        L-phenylalanine. In some embodiments, c_(B) is any amino acid        having a free thiol group. In some embodiments, c_(B) is        D-cysteine. In some embodiments, c_(A) is any amino acid having        a N-terminal amine group. In some embodiments, c_(A) is        D-glutamate. In some embodiments, c_(A) is lysine. In some        embodiments, c_(M) is any amino acid with a side chain capable        of forming an oxime or hydrazone bond upon reaction with a        hydroxylamine or hydrazine group. In some embodiments, c_(M) is        para-4-acetyl L-phenylalanine.

As used herein, “orthogonally reactive” means a plurality of groups canbe attached to a molecule via a sequence of reactions that do not crossreact enabling specific attachment of each group in the presence of theothers. In some embodiments, the three groups (D_(A), D_(B), and D_(M))are able to be attached to A₁-X₁-B₁ via c_(A), c_(B), and c_(M) using asequence of 3 independent reactions that do not cross react so that eachgroup is attached to only one site on A₁-X₁-B₁.

Disclosed herein, in certain embodiments, is a molecule having the aminoacid sequence:

(D-Glu)₅.F(4-Ac)-o-Pro-Leu-Gly-Cys_((Me))-Ala-Gly- (D-Arg)₈-(D-Cys)wherein o represent 5-(amino-3-oxapentanoyl); F_((4-Ac)) representpara-acetyl-(L)-phenylalanine; and C_((Me)) representsS-methyl-(L)-cysteine.

In some embodiments, the molecule further comprises a polyethyleneglycol (PEG) polymer. In some embodiments, the PEG polymer is covalentlylinked to the molecule at the F(4-Ac) subunit. In some embodiments, themolecule comprises groups that can be orthogonally reacted. In someembodiments, the groups that can be orthogonally reacted are chosenfrom: an amine, thiol and an acetyl phenylalanine. In some embodiments,the molecule comprises an amine, a thiol, and an acetyl phenylalanine.

In some embodiments, the PEG polymer has an average molecular weight of500 daltons. In some embodiments, the PEG polymer has an averagemolecular weight of 2,000 daltons. In some embodiments, the PEG polymerhas an average molecular weight of 5,000 daltons. In some embodiments,the PEG polymer has an average molecular weight of 10,000 daltons. Insome embodiments, the PEG polymer has an average molecular weight of20,000 daltons. In some embodiments, the PEG polymer has an averagemolecular weight of 40,000 daltons. Disclosed herein, in certainembodiments, is the use of the molecule in the synthesis of a moleculeaccording to Formula I.

Disclosed herein, in certain embodiments, is a molecule having the aminoacid sequence:

(D-Glu)₅-o-Pro-Leu-Glys-Cys_((me))-Ala-Gly-(D-Arg)₈-(D-Cys)-[PEG_((3K))]wherein all glutamates and arginines are D-amino acids; o represents5-(amino-3-oxapentanoyl); C(me) represents S-methyl-(L)-cysteine; andPEG_((3K)) represents α-amino-ω-amide poly(ethylene glycol) with anaverage three thousand Dalton molecular weight. In some embodiments, themolecule further comprises a fluorescent moiety. Disclosed herein, incertain embodiments, is the use of the molecule in the synthesis of amolecule according to Formula I.

EXAMPLES Materials and Methods

HPLC-grade acetonitrile was purchased from Fisher Scientific(Phillipsburg, Pa.). Purified water was collected through Milli-Q waterpurification system (Millipore, Bedford, Mass.). 3-Maleimidopropionicacid-Pfp ester was purchased from Molecular Biosciences (Boulder,Colo.). PBS-EDTA buffer was purchased from Teknova (Hollister, Calif.).Trifluoroacetic acid (TFA), Dimethylformamide (DMF) andN-methylmorpholine (NMM) were supplied by Sigma-Aldrich (Milwaukee,Wis.). α-Mercaptoethyl-ω-methoxy, poly-oxyethylene (Mw 2,000, 5,000,20,000 and 40,000) [mPEG(2K)-SH, mPEG(5K)-SH, mPEG(20K)-SH,mPEG(40K)-SH] and α-aminoxyl-ω-methoxy, polyoxyethylene (Mw 2,000,5,000, 20,000 and 40,000) [mPEG(2K)-ONH₂, mPEG(5K)-ONH₂, mPEG(20K)-ONH₂,mPEG(40K)-ONH₂] were purchased from NOF America Corporation (Irvine,Calif.). mPEG(1K)-NHNH₂ was purchased from Nanocs (New York). IRDye800CW maleimide (Mal-IRDye) and IRDye 750 succinimidyl ester weresupplied by Li-Cor Biosciences (Lincoln, Nebr.). Lyophilized peptidesP1-P17 were prepared using standard resin based peptide couplingmethods.

LC-MS analysis was carried out on an Agilent 1200 SL series incombination with AB SCIEX API 3200, equipped with CTC PAL autosampleroperating at 4° C., a vacuum degasser, binary pump, UV-VIS detector,associated Analyst 1.5 analytical software and a Phenomenex column(Kinetex 2.6μ C18 100A, 100×2.1 mm) or a Waters 2695 separation moduleequipped with a Waters 2487 dual X absorbance detector in combinationwith Finnigan LCQ Deca XP mass spectrometer. The equipment is associatedwith Xcalibur analytical software and a Peeke Scientific column (Titan200 5 μm, C18-MC, 50×2.1 mm).

Preparation HPLC were carried out on an Agilent system (Agilent 1200series) and a Thermo Scientific column (Hypersil Gold C18, 5μ, 250×10mm), or a Waters Delta Prep preparative HPLC System and a Varian column(F75L, C18, 15μ, 1200 g), or a Waters PrepLC System equipped with aWaters 2487 dual λ absorbance detector, Fraction Collector III, Masslynxsoftware and a Thermo Scientific column (Hypersil Gold C18, 5μ, 250×10mm) or a Phenomenex column (luna, C18(2), 5μ, 100A AX 150×30 mm). Themobile phase consisted of a water (0.05% TFA)(solvent A)/acetonitrile(0.05% TFA)(solvent B) gradient.

Centrifugation was carried out at 4° C. with an Eppendorf centrifuge5810R or a Beckman Microfuge® 18.

Exemplary materials for synthesis of the selective delivery moleculesdisclosed herein include, but are not limited to, any of peptides P-1,P-2, P-3, P-4, P-5, P-6, P-7, P-8, P-9, P-10, P-11, P12, P-13, P-14,P-15, P-16, and P-17.

The above starting materials are summarized below:

Peptide Sequences Peptide P-1 eeeeeeeeeoPLGC_((Me))AGrrrrrrrrrcPeptide P-2 eeeeeoPLGC_((Me))AGrrrrrrrrc Peptide P-3eeeeeF_((4-Ac))oPLGC_((Me))AGrrrrrrrrc Peptide P-4eeeeeeeeeF_((4-Ac))oPLGC_((Me))AGrrrrrrrrrc Peptide P-5(Ac)eeeeeoPLGC_((Me))AGrrrrrrrrck Peptide P-6eeeeeoPLGC_((Me))AGoF_((4-Ac))rrrrrrrrc Peptide P-7eeeeeeeeeoPLGC_((Me))AGrrrrrrrrrcoF_((4-Ac)) Peptide P-8[mPEG_((2K))]crrrrrrrrPLGC_((Me))AGoeeeeek Peptide P-9[mPEG_((5K))]crrrrrrrrPLGC_((Me))AGoeeeeek Peptide P-10eeeeeoPLGC_((Me))AGrrrrrrrrc[PEG_((3K))] Abbreviations: Standard 1letter amino acid abbreviations were used in all the sequences.Lowercase characters indicated D-amino acids. All peptides were amidatedat C-terminus. o: 5-(amino-3-oxopentanoyl); F_((4-Ac)): para-acetyl-(L)-phenylalanine; C_((Me)): S-methyl-(L)-cysteine. PEG(3K): α-amino-ω-amidepoly(ethylene glycol) with an averaged three thousand Daltons molecularweight; PEG(2k): α-carboxy-ω-methoxy poly(ethylene glycol) with anaveraged two thousand Daltons molecular weight; mPEG(5k):α-carboxy-ω-methoxy poly(ethylene glycol) with an averaged five thousandDaltons molecular weight. Ac: acetyl.

Example 1: Synthesis of SDM-2 from Peptide P-1

Synthesis of Intermediate 5

To a solution of peptide P-1 (8 mg, 2.1 μmol) in DMF (0.8 mL) at roomtemperature in the dark were added IRDye 800CW maleimide (2 mg, 1.7μmol) and N-methylmorpholine (10 μL, 91 μmol) with stirring. Thereaction was followed by LC-MS and usually completed in 1 h. The mixturewas directly used in the next step without further purification.

To the reaction mixture above was added 3-maleimidopropionic acid-Pfpester (2 mg, 6.0 μmol). The resulting mixture was stirred at roomtemperature in the dark for 20 h. Purification by RP-HPLC affordedintermediate 5 (2.1 mg, 22% for two steps). Calculated: [M+3H]³⁺(C₁₈₇H₂₉₀N₅₉O₆₄S₆) m/z=1526; Found ESI: [M+3H]³⁺ (C₁₈₇H₂₉₀N₅₉O₆₄S₆)m/z=1526.

Synthesis of Selective Delivery Molecule SDM-2

The mixture of intermediate 5 (1.5 mg, 0.27 μmol) and mPEG(40K)-SH (10mg, 0.25 μmol) in PBS-EDTA buffer (0.5 mL, 137 mM NaCl, 7 mM Na₂HPO₄, 3mM KCl, 1.4 mM K₃PO₄, 4 mM EDTA, pH 7.4) was stirred at room temperaturein the dark for 20 h. Purification by RP-HPLC afforded selectivedelivery molecule SDM-2 (7.0 mg, 61%).

Selective delivery molecules SDM-1, SDM-3, SDM-4, and SDM-5 wereprepared analogously to SDM-2 from peptide P-1.

Example 2: Synthesis of SDM-6 from Peptide P-2

Synthesis of Intermediate 7

To a solution of peptide P-2 (378.5 mg, 0.1 mmol) in DMF (25 mL) at roomtemperature in the dark were added Cy5 maleimide (87 mg, 0.09 mmol) andN-methylmorpholine (350 μL, 3.2 mmol) with stirring. The reaction wasfollowed by LC-MS and completed in 1 h. The mixture was directly used inthe next step without further purification.

To the reaction mixture above was added 3-maleimidopropionic acid-Pfpester (50 mg, 0.15 mmol). The resulting mixture was stirred at roomtemperature in the dark for 5 h. Purification by RP-HPLC affordedintermediate 7 (108 mg, 27% for two steps). Calculated: [M+211]²⁺(C₁₄₈H₂₃₅N₅₁O₄₄S₄) m/z=1780; Found ESI: [M+211]²⁺ (C₁₄₈H₂₃₅N₅₁O₄₄S₄)m/z=1780.

Synthesis of Selective Delivery Molecule SDM-6

The mixture of intermediate 7 (95 mg, 21.2 μmol) and mPEG(40K)-SH (0.9g, 22.5 μmol) in PBS-EDTA buffer (40 mL, 137 mM NaCl, 7 mM Na₂HPO₄, 3 mMKCl, 1.4 mM K₃PO₄, 4 mM EDTA, pH 7.4) was stirred at room temperature inthe dark for 20 h. Purification by RP-HPLC afforded selective deliverymolecule SDM-6 (0.85 g, 90%).

Selective delivery molecules SDM-7 and SDM-8 were prepared analogouslyto SDM-6 from peptide P-2.

Example 3: Synthesis of SDM-25 from Peptide P-3

Synthesis of Intermediate 8

To a solution of peptide P-3 (200 mg, 49.6 μmol) in DMF (5 mL) at roomtemperature in the dark were added Cy5 maleimide (60 mg, 65.6 μmol) andN-methylmorpholine (80 μL, 0.73 mmol) with stirring. The reaction wasfollowed by LC-MS and completed in 1 h. Ether (40 mL) was added to themixture. The precipitate was collected after centrifuge, washed withether (40 mL×2) and purified by HPLC to afford intermediate 8 (141 mg,61%). Calculated: [M+3H]³⁺ (C₁₅₂H₂₄₂N₅₁O₄₃S₄) m/z=1200; Found ESI:[M+3H]³⁺(C₁₅₂H₂₄₂N₅₁O₄₃S₄) m/z=1200.

Synthesis of Intermediate 9

To a solution of intermediate 8 (101 mg, 21.8 μmol) in DMF (10 mL) atroom temperature were added Cy7 carboxylic acid, succinimidyl ester (40mg, 41.1 μmol) and N-methylmorpholine (0.2 mL, 1.8 mmol). The resultingmixture was stirred at room temperature in the dark for 36 h. Ether (35mL) was added to the mixture. The precipitate was collected aftercentrifuge and washed with ether (40 mL×2). Purification of the mixtureby RP-HPLC afforded intermediate 9 (28.1 mg, 25%) and intermediate 8 (63mg). Calculated: [M+3H]³⁺ (C₁₈₇H₂₈₂N₅₃O₅₀S₆)=1421; Found ESI: [M+3H]³⁺(C₁₈₇H₂₈₂N₅₃O₅₀S₆) m/z=1421.

Synthesis of Selective Delivery Molecule SDM-25

The mixture of intermediate 9 (28.1 mg, 5.4 μmol) and mPEG(2K)-ONH₂ (17mg, 7.6 μmol) in glycine buffer (4 mL, 0.1 M, 20 mM aniline, pH 3.0) andacetonitrile (0.8 mL) was stirred at room temperature in the dark for 24h. After the reaction was complete, acetophenone (10 μL, 86 μmol) wasadded. The mixture was stirred at room temperature for 2 h. Purificationby RP-HPLC afforded selective delivery molecule SDM-25 (25 mg, 63%).

Selective delivery molecules SDM-9, SDM-10, SDM-22, SDM-23, SDM-24,SDM-26, SDM-27, SDM-29 and SDM-31 were prepared analogously to SDM-25from peptide P-3.

Example 4: Synthesis of SDM-15 from Peptide P-4

Synthesis of Intermediate 11

To a solution of peptide P-4 (30 mg, 6.2 μmol) in DMF (2 mL) at roomtemperature in the dark were added Cy5 maleimide (7.5 mg, 8.2 μmol) andN-methylmorpholine (15 μL, 0.14 mmol) with stirring. The reaction wasfollowed by LC-MS and completed in 1 h. The mixture was purified by HPLCto afford intermediate 11 (19.7 mg, 59%). Calculated: [M+3H]³⁺(C₁₇₈H₂₈₂N₅₉O₅₆S₄) m/z=1424; Found ESI: [M+3H]³⁺ (C₁₇₈H₂₈₂N₅₉O₅₆S₄)m/z=1424.

Synthesis of Intermediate 12

To a solution of intermediate 11 (15 mg, 2.8 μmol) in DMF (1.5 mL) atroom temperature were added Cy7 carboxylic acid, succinimidyl ester (4mg, 4.3 μmol) and N-methylmorpholine (10 μL, 91 μmol). The resultingmixture above was stirred at room temperature in the dark for 48 h.Purification by RP-HPLC afforded intermediate 12 (5.0 mg, 30%).Calculated: [M+3H]³⁺ (C₂₁₃H₃₂₂N₆₁O₆₃S₆) m/z=1645; Found ESI: [M+3H]³⁺(C₂₁₃H₃₂₂N₆₁O₆₃S₆) m/z=1645.

Synthesis of Selective Delivery Molecule SDM-15

The mixture of intermediate 12 (1.1 mg, 0.18 μmol) and mPEG(2K)-ONH₂ (1mg, 0.5 μmol) in glycine buffer (1 mL, 0.1 M, 20 mM aniline, pH 3.0) andacetonitrile (0.2 mL) was stirred at room temperature in the dark for 1day. Purification by RP-HPLC afforded selective delivery molecule SDM-15(0.6 mg, 42%).

Selective delivery molecules SDM-11, SDM-12, SDM-13, SDM-14 and SDM-28were prepared analogously to SDM-15 from intermediate 11.

Example 5: Synthesis of SDM-16 from Peptide P-5

Synthesis of Intermediate 20

To a solution of peptide P-5 (20 mg, 5.2 μmol) in DMF (1 mL) at roomtemperature in the dark were added Cy5 maleimide (6 mg, 6.6 μmol) andN-methylmorpholine (12 μL, 109 μmol) with stirring. The reaction wasfollowed by LC-MS and usually completed in 1 h. The mixture was directlyused for the next step without further purifications. To a solution ofthe above mixture in DMF (1 mL) at room temperature was added3-maleimidopropionic acid-Pfp ester (2.5 mg, 7.5 μmol). The resultingmixture above was stirred at room temperature in the dark for 20 h.Purification by RP-HPLC afforded intermediate 20 (7.3 mg, 30% for twosteps). Calculated: [M+3H]³⁺ (C₁₅₆H₂₅₀N₅₃O₄₆S₄) m/z=1244; Found ESI:[M+3H]³⁺ (C₁₅₆H₂₅₀N₅₃O₄₆S₄) m/z=1244.

Synthesis of Selective Delivery Molecule SDM-16

The mixture of intermediate 20 (1.4 mg, 0.3 μmol) and mPEG(40K)-SH (14mg, 0.35 μmol) in PBS-EDTA buffer (2 mL, 137 mM NaCl, 7 mM Na₂HPO₄, 3 mMKCl, 1.4 mM K₃PO₄, 4 mM EDTA, pH 7.4) was stirred at room temperature inthe dark for 20 h. Purification by RP-HPLC afforded selective deliverymolecule SDM-16 (6.5 mg, 49%).

Selective delivery molecules SDM-17, SDM-18 were prepared analogously toSDM-16 from peptide P-5.

Example 6: Synthesis of SDM-33 from Peptide P-7

Synthesis of Intermediate 21

To a solution of peptide P-7 (20 mg, 4.1 μmol) in DMF (1 mL) at roomtemperature in the dark were added Cy5 maleimide (6 mg, 6.6 μmol) andN-methylmorpholine (10 μL, 91 μmol) with stirring. The reaction wasfollowed by LC-MS and completed in 1 h. The mixture was purified byRP-HPLC to afford intermediate 21 (9 mg, 40%). Calculated: [M+3H]³⁺(C₁₈₂H₂₈₉N₆₀O₅₈S₄) m/z=1458; Found ESI: [M+3H]³⁺ (C₁₈₂H₂₈₉N₆₀O₅₈S₄)m/z=1458.

Synthesis of Intermediate 22

To a solution of intermediate 21 (9 mg, 1.6 μmol) in DMF (1 mL) at roomtemperature were added Cy7 carboxylic acid, succinimidyl ester (3 mg,3.1 μmol) and N-methylmorpholine (10 μL, 91 μmol). The resulting mixtureabove was stirred at room temperature in the dark for 24 h. Purificationby RP-HPLC afforded intermediate 22 (4.9 mg, 50%). Calculated: [M+3H]³⁺(C₂₁₇H₃₂₉N₆₂O₆₅S₆) m/z=1679; Found ESI: [M+3H]³⁺ (C₂₁₇H₃₂₉N₆₂O₆₅S₆)m/z=1679.

Synthesis of Selective Delivery Molecule SDM-33

The mixture of intermediate 22 (0.9 mg, 0.15 μmol) and mPEG(10K)-ONH₂ (3mg, 0.3 μmol) in glycine buffer (1 mL, 0.1 M, 20 mM aniline, pH 3.0) andacetonitrile (0.2 mL) was stirred at room temperature in the dark for 3days. After the reaction was complete, acetophenone (10 μL, 86 μmol) wasadded. The mixture was stirred at room temperature for 2 h. Purificationby RP-HPLC afforded selective delivery molecule SDM-33 (0.8 mg, 38%).

Selective delivery molecule SDM-34 was prepared analogously to SDM-33from intermediate 22.

Example 7: Synthesis of SDM-36 from Peptide P-8

Synthesis of Intermediate 23

To a solution of peptide P-8 (10 mg, 1.7 μmol) in DMF (1 mL) at roomtemperature in the dark were added Cy5 maleimide (4 mg, 4.4 μmol) andN-methylmorpholine (10 μL, 91 μmol) with stirring. The reaction mixturewas stirred at room temperature in 1 h. Purification by RP-HPLC affordedintermediate 23 (5.4 mg, 48%).

Synthesis of Selective Delivery Molecule SDM-36

To a solution of intermediate 23 (5.4 mg, 0.82 μmol) in DMF (1 mL) atroom temperature were added Cy7 carboxylic acid, succinimidyl ester (3mg, 3.1 μmol) and N-methylmorpholine (10 μL, 91 μmol). The resultingmixture above was stirred at room temperature in the dark for 36 h.Purification by RP-HPLC afforded SDM-36 (0.7 mg, 13%).

Selective delivery molecules SDM-37 was prepared analogously to SDM-36from peptide P-8.

Example 8: Synthesis of SDM-38 from Peptide P-10

Synthesis of Intermediate 24

To a solution of peptide P-10 (10 mg, 1.4 μmol) in PBS buffer (pH 7.4, 1mL) at room temperature in the dark were added Cy5 maleimide (4 mg, 4.4μmol) with stirring. The reaction mixture was stirred at roomtemperature in 1 h. Purification by RP-HPLC afforded intermediate 24(7.9 mg, 79%).

Synthesis of Selective Delivery Molecule SDM-38

To a solution of intermediate 24 (7.9 mg, 1.1 μmop in DMF (1 mL) at roomtemperature were added Cy7 carboxylic acid, succinimidyl ester (2 mg,2.0 μmol) and N-methylmorpholine (10 μL, 91 μmol). The resulting mixtureabove was stirred at room temperature in the dark for 36 h. Purificationby RP-HPLC afforded selective delivery molecules SDM-38 (1.7 mg, 19%).

Selective delivery molecules SDM-39 was prepared analogously to SDM-38from peptide P-10.

Example 9: Synthesis of SDM-40 from Peptide P-8

Synthesis of Intermediate 25

To a solution of peptide P-8 (10 mg, 1.7 μmol) in DMF (1 mL) at roomtemperature in the dark were added Cy7 maleimide (4 mg, 4.2 μmol) andN-methylmorpholine (10 μL, 91 μmol) with stirring. The reaction mixturewas stirred at room temperature in 1 h. Purification by RP-HPLC affordedintermediate 23 (3.1 mg, 28%).

Synthesis of Selective Delivery Molecule SDM-40

To a solution of intermediate 23 (3.1 mg, 0.47 μmol) in DMF (1 mL) atroom temperature were added Cy5 carboxylic acid, succinimidyl ester (2mg, 2.1 μmol) and N-methylmorpholine (5 μL, 46 μmol). The resultingmixture above was stirred at room temperature in the dark for 24 h.Purification by RP-HPLC afforded SDM-40 (1.4 mg, 41%).

Example 10: Synthesis of SDM-30 from Peptide P-3

Synthesis of Intermediate 26

The mixture of intermediate 8 (3 mg, 0.64 μmol) and Cy7-ONH₂ (3 mg, 2.9μmol) in glycine buffer (4 mL, 0.1 M, 20 mM aniline, pH 3.0) andacetonitrile (0.1 mL) was stirred at room temperature in the dark for 36h. Purification by RP-HPLC afforded intermediate 26 (1.1 mg, 31%).Calculated: [M+3H]³⁺ (C₁₈₉H₂₈₈N₅₅O₅₀S₆) m/z=1441; Found ESI: [M+3H]³⁺(C₁₈₉H₂₈₈N₅₅O₅₀S₆) m/z=1441. Cy7-ONH₂ was prepared from Cy7-COOH and2-[N-phthalimido-(aminooxy)]ethanamine under standard amide couplingconditions followed by the removal of the phthalimide protecting groupwith hydrazine. 2-[N-phthalimido-(aminooxy)]ethanamine was prepared fromcommercially available N-Boc-ethanolamine and N-hydroxyphthalimidethrough a Mitsunobu reaction followed by the cleavage of Boc group withTFA.

Synthesis of Intermediate 27

To a solution of intermediate 26 (1.1 mg, 0.2 μmol) in DMF (1 mL) atroom temperature were added 3-maleimidopropionic acid-Pfp ester (0.5 mg,1.5 μmol) and N-methylmorpholine (5 μL, 45 μmol). The resulting mixtureabove was stirred at room temperature in the dark for 36 h. Purificationby RP-HPLC afforded intermediate 27 (0.8 mg, 75%). Calculated: [M+3H]³⁺(C₁₉₆H₂₉₁N₅₆O₅₃S₆) m/z=1491; Found ESI: [M+3H]³⁺ (C₁₉₆H₂₉₁N₅₆O₅₃S₆)m/z=1491.

Synthesis of Selective Delivery Molecule SDM-30

The mixture of intermediate 27 (0.7 mg, 0.15 μmol) and mPEG(10K)-SH (3mg, 0.3 μmol) in PBS-EDTA buffer (0.5 mL, 137 mM NaCl, 7 mM Na₂HPO₄, 3mM KCl, 1.4 mM K₃PO₄, 4 mM EDTA, pH 7.4) was stirred at room temperaturein the dark for 40 h. Purification by RP-HPLC afforded selectivedelivery molecule SDM-30 (1.2 mg, 23%).

Selective delivery molecules SDM-32 and SDM-35 were prepared analogouslyto SDM-30 from peptides P-3 and P-4.

Example 11: Synthesis of SDM-21 from Peptide P-6

Synthesis of Intermediate 28

To a solution of peptide P-6 (30 mg, 7.6 μmol) in DMF (2 mL) at roomtemperature in the dark were added Cy5 maleimide (9 mg, 9.4 μmol) andN-methylmorpholine (15 μL, 137 μmol) with stirring. The reaction wasfollowed by LC-MS and completed in 1 h. Purification by RP-HPLC affordedintermediate 28 (24.9 mg, 68%). Calculated: [M+3H]³⁺ (C₁₅₆H₂₄₉N₅₂O₄₅S₄)m/z=1233; Found ESI: [M+3H]³⁺ (C₁₅₆H₂₄₉N₅₂O₄₅S₄) m/z=1233.

Synthesis of Intermediate 29

To a solution of intermediate 28 (17.7 mg, 3.7 μmol) in DMF (1.5 mL) atroom temperature were added Cy7 carboxylic acid, succinimidyl ester (5mg, 5.5 μmol) and N-methylmorpholine (20 μL, 0.18 mmol). The resultingmixture was stirred at room temperature in the dark for 30 h.Purification of the mixture by RP-HPLC afforded intermediate 29 (7.1 mg,35%). Calculated: [M+3H]³⁺ (C₁₉₁H₂₈₉N₅₄O₅₂S₆) m/z=1455; Found ESI:[M+3H]³⁺ (C₁₉₁H₂₈₉N₅₄O₅₂S₆) m/z=1455.

Synthesis of Selective Delivery Molecule SDM-21

The mixture of intermediate 29 (1.8 mg, 0.33 μmol) and mPEG(10K)-ONH₂ (4mg, 0.4 μmol) in glycine buffer (1 mL, 0.1 M, 20 mM aniline, pH 3.0) andacetonitrile (0.1 mL) was stirred at room temperature in the dark for 3days. Purification by RP-HPLC afforded selective delivery moleculeSDM-21 (1.0 mg, 20%).

Selective delivery molecules SDM-19 and SDM-20 were prepared analogouslyto SDM-21 from intermediate 29.

Example 12: Enzyme Dependent Fluorescence Enhancement and Color Changes

Selective delivery molecule 9 was dissolved in TCNB buffer (50 mM Tris,pH 7.5, with 10 mM calcium chloride, 150 mM sodium chloride, and 0.05%BRIJ 35) at room temperature at 1 μM. Fluorescence spectra were recordedon F-2500 fluorescence spectrometer. The Cy5 fluorescence donor wasexcited using 625 nm light and the emission was scanned from 660 to 800nm. The Cy5 donor emission peaked at ˜670 nm and the Cy7 FRET acceptoremission peak was ˜780 nm as shown in FIG. 2. Peptide cleavage wasinitiated with addition of matrix metalloproteinase-2 (MMP-2) at a finalconcentration of 1 nM. The cleavage reaction was complete within 2 hourand the fluorescence spectra indicated FRET disruption and a large8-fold increase the Cy5 donor emission and 2-fold decrease in the Cy7emission. The actual intrinsic fluorescence decrease of Cy7 is largerhowever it is masked by the Cy5 long wavelength shoulder. This resultdemonstrates that SDM-9 has efficient energy transfer from Cy5 to Cy7 inthe intact peptide.

Example 13: Enzyme Dependent Fluorescence Enhancement and Color Changes

Selective delivery molecule 10 was dissolved in TCNB buffer (pH 7.5) atroom temperature at 1 μM. Fluorescence spectra were recorded on F-2500fluorescence spectrometer. Excitation of the Cy5 fluorescence donor wasexcited at 625 nm and the emission was measured at 669 nm. Peptidecleavage was initiated with addition of MMP-9 at a final concentrationof 1 nM. The cleavage reaction was complete within 2 hour and thefluorescence was enhanced >100-fold upon protease cleavage, FIG. 3. Thelarge fluorescence response demonstrates that the dye quencherefficiently quenches the Cy5 fluorophore in the uncleaved SDM-10.

Example 14: Fluorogenic Response from Tumor Homogenates

HT1080 cells (Cat. # CCL-121; American Type Culture Collection, Va.,USA) were grown under exponential growth conditions in humidifiedatmosphere of 5% CO₂ in air at 37° C. until reaching 80-100% confluencebefore harvesting for mouse implantation. Each nude mouse was handrestrained and injected with 2×10⁶ HT-1080 cells into the mammary fatpad using a 25-G needle. HT-1080 tumors were harvested when they hadreached 100-200 mm³ in size (typically 1-2 weeks post-tumor cellsimplantation).

HT-1080 tumors were homogenized using ultrasonic disruption. 1 nM MMP-9or 10 μl, tumor tissue homogenates (TH2 and TH3) were mixed with 1 μMSDM-10 in 100 μL buffer for 24 h at 37° C. Selective delivery molecule 6was used as a fluorescent control of similar size to intact SDM-10. Thesamples were loaded on a polyacrylamide gel and separated usingelectrophoresis. The data are shown in FIG. 4 and demonstrate thatSDM-10 is essentially non-fluorescent prior to cleavage. Afterincubation with HT-1080 tumor homogenates, SDM-10 is cleaved and becomeshighly fluorescent. GM6001 is a general broad spectrum inhibitor ofMMPs. The fact that GM6001 inhibits cleavage demonstrates that thehomogenate cleavage is due to tumor associated MMPs.

Example 15: In Vivo Imaging Assay for Tumor Contrast

HT-1080 xenograft model was generated as described in Example 14 andused to evaluate the ability of molecules to provide in vivo tumorfluorescence contrast compared to surrounding tissue. Fluorescentconjugates were tested in HT-1080 tumor-bearing mice once the tumors hadreached 100-200 mm³ in size (typically 1-2 weeks post-tumor cellsimplantation). Conscious HT-1080 tumor-bearing mice were restrainedusing a rotating tail injector (Cat.# RTI; Braintree Scientific, MA,USA) and dosed intravenously (tail vein) with the test compound atbetween 0.1 and 5 nanomoles per mouse in 100 uL saline solution. Inpreparation for imaging, mice were lightly anesthetized with a mixtureof ketamine/xylazine (Cat.# K-113; Sigma, Aldrich, Mo., USA) givenintraperitoneally (1 μL/gram body weight) to minimize movement.

Serial whole-body imaging (tumor included) was done using a whole-animalfluorescent visualization imaging system or Olympus stereo fluorescentmicroscope. The mice were positioned on their backs and imaging wasperformed from the top to image the ventral side of the animal.Excitation and emission wavelengths were selected based on thefluorescent dye used. Contrast was calculated using the followingequation:

Contrast=(Fluorescence intensity of tumor−Fluorescence intensity ofcontralateral chest tissue)/Intensity of contralateral chest tissue).

Contrast greater than 0.4 in the whole animal is easily detected by eyein the whole animal image and is good contrast. Contrast >0.7 is highcontrast.

The mice were imaged several times between 1-24 hours after injection.

Representative imaging data two hours after dosing for selectivedelivery molecule 6 in 3 different mice is shown in FIG. 1. In thisparticular image the mean contrast is 1.1. Other compounds were testedin a similar fashion and the contrast results are given in table 1.

TABLE 1 Summary of peptide conjugate in vivo contrast data from HT-1080xenograft model. Selective Time to maximum delivery Maximum Contrastcontrast (hr) (very fast <4; molecule (≥0.4 = good; ≥0.9 = high) 4 <fast < 12; >12 slow) 1 Good Fast 2 High Fast 3 High Slow 4 5 6 High VeryFast 7 High Slow 8 Good Very fast 9 High Fast

Example 16: In Vivo Distribution and Compounds with Improved TissueAccumulation

To determine the total dye accumulation in various organs, HT-1080xenograft mice were sacrificed and tissue samples from blood, liver,kidney, and tumor were collected 6 hours after compounds wereadministered iv via the tail vein. 3-4 mice were used for each datapoint. Blood samples were stored at 4° C. overnight and then centrifugedat 15,000 rpm to separate out the serum. The organs were mixed in a ProKbuffer (0.25 mg/ml Prok, 0.1 mg/ml DNAse, 150 mM NaCl, 10 mM Tris pH8.0,0.2% SDS) at 10 μL/mg tissue and cut into small pieces using scissors.The tissue/digest solution was then sonicated for 1 minute at 67% dutycycle and digested overnight at 37° C. After digestion, the sample wascentrifuged at 15,000 rpm and the tissue homogenate was aspirated offand stored at 4° C.

The tissue concentration of fluorescent compounds were determined fromfluorescence standard curves generated by spiking in know concentrationsof administered compounds into serum and tissue homogenates (at variousdilutions) from control animals that were not injected with compound.The linear range for each compound was determined for each tissue.Fluorescence measurements were done on either a fluorescent plate readeror fluorescence spectrometer. The tissue biodistribution results fromselective delivery molecules 1, 2, and 6 are shown in FIG. 5. Asurprising result was that selective delivery molecule 6 has 5-foldhigher tissue distribution into tumor compared to selective deliverymolecules 1 and 2. This unexpected result is due to the asymmetric corecomposed of uneven numbers of positively and negatively charged peptidebackbone. Selective delivery molecules 1 and 2 have equal numbers givinga net neutral core while selective delivery molecule 6 has a net 3+charge due to more positively charged arginines. This demonstrates thatcompounds with different number of acidic and basic amino acids haveimproved and useful in vivo and biodistribution properties oversymmetric molecules.

Example 17: In Vivo Detection of Cancer Metastases to Lymph Node withFRET SDMs Fluorescence Labeling of Metastatic Cervical Lymph NodesFollowing Intravenous and Peritumoral Administration of Fluorescent SDMsin Tumor Bearing Mice

The following model and assays were used to determine the ability offluorescent SDMs to detect cancer metastases to lymph nodes inimmunocomptent BALB/c mice (Charles River, Wilmington, Mass. 01887)bearing syngeneic ear tumors.

Mouse Model.

The mice were housed in groups of 4 in individually ventilated IVCdisposable cages (Innovive, Inc., San Diego, Calif. 92121) and had freeaccess to standard laboratory chow (Cat. #2018, Harlan Laboratories,Inc. Indianapolis, Ind. 46250) and drinking water. Animals were keptunder controlled environmental conditions (12-h/12-h light/dark cycle)for at least 5 days before tumor cell implantation. All experimentalprocedures were carried out under the approved IACUC protocol #EB11-002-009A. Murine 4T1 tumor (ATCC® Number: CRL-2539™) and mammarycarcinoma (Polyoma Middle T 8119 subclone “PyMT 8119”) cells from theAmerican Type Culture Collection (ATCC, Manassas, Va. 20108) and theUniversity of San Diego, Calif. (UCSD, La Jolla, Calif. 92093)respectively were grown separately using standard cell culturetechniques. Tumor cells (4×10⁵ tumor cells/50 μL/mouse) were suspendedin DPBS/Matrigel™ (1:1 vol) and injected subcutaneously on the mouse earpinna above the auricular cartilage for primary tumor induction. The invivo imaging of metastatic cervical lymph nodes in ear tumor-bearingmice used as surrogate murine model of metastatic breast cancer tookplace seventeen to twenty days following tumor cell implantation.

Test SDM Compound Administration.

For the intravenous administration (tail vein injection) of SDMs, micewere restrained in a rotating tail injector (Cat.# RTI, BraintreeScientific, Inc., Braintree, Mass. 02185) and the test article (5-120μM; 100 μL/mouse) injected in mouse using a 28G^(1/2) insulin syringe(Cat. #14-826-79, Becton Dickinson and Company, Franklin Lakes, N.J.07417). To perform the peritumoral injection of SDMs, each involvedmouse was sedated using the ketamine/xylazine (Ketaject® & Xyla-ject®,Phoenix Pharmaceuticals, St. Joseph, Mo. 64506) mixture administeredintraperitoneally and the test article (5-120 μM; 30-60 μL/ear) injectedsubcutaneously around the primary tumor and contralateral ear pinnausing a 30G PrecisionGlide™ needle (Cat. #305106, Becton Dickinson andCompany, Franklin Lakes, N.J. 07417). After dosing, each mouse wasreturned to the assigned cage and kept under controlled environmentalconditions before imaging. Fluorescence imaging of cervical lymph nodes1-24 hours after compound administration as described below.

Fluorescence Imaging.

To image the cervical lymph nodes, each mouse was deeply anesthetizedwith a mixture of ketamine/xylazine administered intraperitoneally. Thedeeply anesthetized mouse was transferred on a piece of black cork (4×4inches, Quartet®, ACCO Brands, Lincolnshire, Ill. 60069, USA) for bluntdissection and imaging of cervical lymph nodes using a computerizedfluorescent stereomicroscope (SZX10, Olympus Optical, CO, LTD, Japan)equipped with appropriate fluorescence filters for both single intensityand two fluorophore fluorescence ratio detection. For example, filtersfor Cy5 and Cy7 were used for FRET-based SDMs with Cy5 and Cy7 FRETpair. After in vivo fluorescence imaging (see below for ratio imagingmethod), the cervical lymph nodes were surgically removed, fixed in 10%buffered formalin and processed for histology (Hematoxylin & Eosinstaining) to assess the fluorescence/cancer correlation and determinediagnostic performance of SDMs.

Emission Ratio Imaging Method.

Fluorescence images were acquired using an Olympus SZX10 Research StereoMicroscope (Olympus America, Center Valley, Pa.). For Cy5 and Cy7FRET-based SDMs an excitation filter centered at 620 nm (ChromaET620/60x, Chroma Technology Corp. Bellows Falls, Vt.) and emissionfilters centered at 700 nm and 810 nm (Chroma filters ET700/75m andET810/90m) were used to produce two images at different emissionwavelengths. Images were acquired with an Orca-R2 camera (Hamamatsu,Bridgewater, N.J.) connected to a Windows-based computer. Two methodswere used to determine emission ratios for lymph nodes. For one methodthe intensity was averaged over a region of interest (ROI) drawn toinclude part or all of the lymph node of interest. The Emission ratiowas then calculated from the intensity data for each region of interest.

Roi EmissionRatio=(roiInt1/Exp1)/(Int2/Exp2)  (equation 1) where

roiInt1=averaged intensity for ROI at emission wavelength 1 withET700/75m filter

Exp1=exposure time used for Int1

roiInt 2=average intensity for ROI at emission wavelength 2 withET810/90m filter

Exp 2=exposure time used for Int2

A second method used to determine emission ratios was based averagingthe emission ratio from a region of interest (ROI) drawn to include partor all of the lymph node of interest taken from an emission ratio image.Emission ratio images were produced by using a modified form of equation1 that included a scaling factor so that the pixel values would fallbetween 0 and 255 for an 8-bit image.

Px EmissionRatio=k*(pxInt1/Exp1)/(pxInt2/Exp2)  (equation 2)

where

k=scaling factor

pxInt1=pixel intensity at emission wavelength 1 with ET700/75m filter

Exp1=exposure time used for Int1

pxInt 2=pixel intensity at emission wavelength 2 with ET810/90m filter

Exp 2=exposure time used for Int2

Emission ratios for lymph nodes gave quantitatively similar resultsusing either method.

Lymph nodes were identified as either metastatic or non-metastatic by apathologist based on H&E staining. Emission ratio contrast for each SDM(selective delivery molecule) was then quantified by dividing theaverage emission ratio of the metastatic nodes by the average emissionof the non-metastatic nodes and subtracting one as shown in equation 3:

ERC=MetAV/ConAV−1  (Equation 3) where

ERC=emission ratio contrast

MetAV=average metastatic lymph node emission ratio

ConAV=average non-metastatic contralateral lymph node emission ratio

An example of an emission ratio image is shown in FIG. 6. The right handpanel show the ratio image which show high contrast between themetastatic lymph node (very large node indicated with lower left darkarrow) and the non-metastatic nodes (other arrows). The higher ratio isshown as lighter pixels (metastatic) compared to darker lower ratiopixels for the non-metastic nodes.

Useful for detecting cancerous lymph nodes, a contrast of 20 to 50% wasconsidered good, an increase of 50 to 100% was considered high, while anincrease greater than 100% was considered to be very high contrast.

TABLE 2 Summary of SDMs in vivo ratio contrast data from Murine 4T1tumor model. Peritumor Maximum IV Maximum Contrast (Low <20%, Contrast(Low <20%, Good Good 20% to 50%, Selective delivery 20% to 50%,High >50% High >50% to 100%, molecule to 100% Very High >100%) VeryHigh >100%) SDM-9 nd Low SDM-11 nd Low SDM-12 nd Good SDM-13 Good GoodSDM-14 Good Very High SDM-19 Good SDM-20 Low SDM-21 nd Good SDM-22 LowSDM-23 High Very High SDM-24 Very High Very High SDM-25 Very High VeryHigh SDM-27 Very High nd SDM-28 Good High SDM-29 nd High SDM-30 nd VeryHigh SDM-31 Low nd SDM-32 Very High Very High SDM-33 Low High SDM-35Very High Good SDM-36 High Good SDM-37 Low nd SDM-38 Good nd SDM-39 GoodHigh SDM-40 nd High

Example 18: Ex Vivo Mouse PyMT 8119 Tumor Activity Assay: SDM Cleavageand FRET Emission Ratio Response in Mouse Cancer Tissue Compared to NonCancerous Tissue

Tumor and muscle tissue samples from PyMT 8119 tumor bearing mice werecollected and frozen at −80° C. The tissues were thawed and homogenizedin cold TCNB buffer (pH 7.5, 50 mM Tris-HCl, 10 mM CaCl₂, 150 mM NaCland 0.05% Brij35) at 100 mg/200 μL using ultrasonic disruption (VCX500,Sonics & Materials Inc, Newtown, Conn.). After homogenates werecentrifuged at 15,000 g at 4° C. for 20 min, supernatants werecollected. APMA (p-aminophenylmercuric acetate, 90 μL, 2 mM in TCNBbuffer) was added to the supernatants (90 μL). The resulting mixtureswere incubated at 37° C. for 1 h before use. 500 nM of SDM-23 was usedfor the cleavage of 45 μL of activated tissue supernatants (finalvolume: 50 μL). The assay was carried out using a SpectraMax M2spectrometer with SoftMax Pro v4.5 software. Fluorescence signals of(λex, 620 nm, λem, 670 nm), (λex, 620 nm, λem, 773 nm) and (λex, 720 nm;λem, 773 nm), where λex and λem stand for excitation and emissionwavelengths respectively, were measured as a function of time at roomtemperature. Samples were measured in triplicate and the FRET SDMcleavage resulted in an increased Cy5/Cy7 fluorescence emission ratiowhere Cy5 signal used (λex, 620 nm, λem, 670 nm) and Cy7 (λex, 620 nm,λem, 773 nm) experimental conditions.

Enzymatic activity from the tissues resulted in SDM-23 cleavage andgenerated a large FRET emission ratio increase (labeled primary tumor),as shown in FIG. 7. The ratio increase is the result of SDM cleavage.These data show that SDM-23 is very active in mouse breast cancertissues and cleavage is significantly greater in cancerous tissuecompared to normal muscle, which shows not activity in this assay.

Example 19: Human Ex Vivo Tissue Assay: SDM Cleavage and FRET EmissionRatio Response in Human Cancer Tissue Compared to Noncancerous Tissue

Human breast cancer tissue samples and normal human breast tissue(provided by Cancer Human Tissue Network) were homogenized in cold TCNBbuffer (pH 7.5, 50 mM Tris-HCl, 10 mM CaCl₂, 150 mM NaCl and 0.05%Brij35) at 100 mg/200 μL using ultrasonic disruption (VCX500, Sonics &Materials Inc, Newtown, Conn.). After homogenates were centrifuged at15,000 g at 4° C. for 20 min, supernatants were collected. 500 nM of SDMwas used for the cleavage of 45 uL of tissue supernatant (final volume:50 μL) in the assay unless otherwise noted. The assay was carried outusing a SpectraMax M2 spectrometer with SoftMax Pro v4.5 software.Fluorescence signals of (λex, 620 nm, λem, 670 nm), (λex, 620 nm, λem,773 nm) and (λex, 720 nm; λem, 773 nm), where λex and λem stand forexcitation and emission wavelengths respectively, were measured as afunction of time at room temperature. Samples were measured intriplicate and the FRET SDM cleavage resulted in an increased Cy5/Cy7fluorescence emission ratio where Cy5 signal used (λex, 620 nm, λem, 670nm) and Cy7 (λex, 620 nm, λem, 773 nm) experimental conditions. Anexample using SDM-25 is shown in FIG. 8. Other SDMs were evaluated usingthe same procedure. The cleavage dependent fluorescence response canalso be quantified as the rate of cleavage (delta ratio per time), asshown in FIG. 9 for SDM-25 and SDM-32. The rates were calculated fromthe slope of the data from time 0 to 300 minutes.

Example 20: High Diagnostic Sensitivity and Specificity for an SDM in aMetastatic Lymph Node Model

Key performance metrics of a diagnostic agent are sensitivity andspecificity. Sensitivity relates to the ability to correctly diagnosetest positives. While specificity relates to the ability to correctlydiagnose test negatives.

As an example of high diagnostic performance of a FRET SDM, we use datagenerated from SDM-24 in the 4T1 mouse metastatic lymph model. SDM-24was administered via IV tail vein injection. After 3 to 6 hours, themice lymph nodes were imaged using fluorescence ratio imaging asdescribed previously to determine whether or not the lymph node had ahigh ratio (diagnosed cancer positive) or low ratio (diagnosed cancernegative). Sensitivity and specificity was determined using receiveroperating characteristic (ROC) or ROC curves(http://en.wikipedia.org/wiki/Receiver_operating_characteristic). ForROC curve analysis, data is divided into a binary classification ofpositives and negatives based on a threshold value for the emissionratio. The ROC curve plots true positive fraction of positives (truepositive rate) versus false positive fraction of negatives (falsepositive rate).

True positives, false positives, true negatives, and false negativeswere determined by comparing the prediction based on the fluorescenceemission ratio data and threshold value with the positive or negativeassignment made by a pathologist using H&E staining. The emission ratiovalues for the cancer positive and negatives (as determined by H&Ehistopathology) are shown in FIG. 10. The threshold value was graduallyadjusted from low to high to obtain a full ROC curve from (1, 1) or allpositives to (0, 0) or all negatives. A ROC curve is shown in FIG. 11.Data from 48 lymph nodes were used to generate this curve. Note thatsensitivity and specificity can be determined for each point in the ROCcurve. Sensitivity is the true positive rate while specificity is oneminus the false positive rate. Equations used to generate the ROC curveare shown below.

TPR=TP/(TP+FN)

FPR=FP/(FP+TN)

Where:

TPR=true positive rate

FPR=false positive rate

TP=# of true positives

TN=# of true negatives

FP=# of false positives

FN=# of false negatives

In this example both sensitivity and specificity are 100% for allthreshold values between 5.65 and 7.15. This means that all lymph nodeswere correctly identified with the FRET emission ratio method whencompared to the gold standard histopathology. Generally, sensitivity andspecificity values >90% are considered very high.

Example 21: Use of an SDM to to Visualize Cancer in Breast CancerPatients

SDM-25 is delivered intravenously to a breast cancer patient. Thefluorescent moieties on SDM-25 are taken up by cancerous cells and/ortissue after cleavage of the linker. A light source is shined onto thetarget tissue. The fluorescent moieties emit light which is detected bya camera or a detector. The data obtained by the camera or detector isprocessed to generate an image that allows the surgeon to visualizecancerous cells or tissue. The surgeon excises said tissue for biopsy.

Example 22: Use of an SDM to to Visualize Cancer in Prostate CancerPatients

SDM-26 is delivered intravenously to a prostate cancer patient. Thefluorescent moieties on SDM-26 are taken up by cancerous cells and/ortissue after cleavage of the linker. A light source is shined onto thetarget tissue. The fluorescent moieties emit light wihich is detected bya camera or a detector. The data obtained by the camera or detector isprocessed to generate an image that allows the surgeon to visualizecancerous cells or tissue. The surgeon excises said tissue for biopsy.

Example 23: Use of an SDM to to Visualize Cancer in Patients with Headand Neck (Squamous) Cancer

SDM-27 is delivered intravenously to a head and neck cancer patient. Thefluorescent moieties on SDM-27 are taken up by cancerous cells and/ortissue after cleavage of the linker. A light source is shined onto thetarget tissue. The fluorescent moieties emit light wihich is detected bya camera or a detector. The data obtained by the camera or detector isprocessed to generate an image that allows the surgeon to visualizecancerous cells or tissue. The surgeon excises said tissue for biopsy.

Example 24: Use of an SDM to to Visualize Cancer in Patients withMelanoma

SDM-24 is delivered intravenously to a patient having melanoma. Thefluorescent moieties on SDM-24 are taken up by cancerous cells and/ortissue after cleavage of the linker. A light source is shined onto thetarget tissue. The fluorescent moieties emit light wihich is detected bya camera or a detector. The data obtained by the camera or detector isprocessed to generate an image that allows the surgeon to visualizecancerous cells or tissue. The surgeon excises said tissue for biopsy.

Example 25: Use of an SDM to to Visualize Cancer in Patients withThyroid Cancer

SDM-32 is delivered intravenously to a thyroid cancer patient. Thefluorescent moieties on SDM-32 are taken up by cancerous cells and/ortissue after cleavage of the linker. A light source is shined onto thetarget tissue. The fluorescent moieties emit light wihich is detected bya camera or a detector. The data obtained by the camera or detector isprocessed to generate an image that allows the surgeon to visualizecancerous cells or tissue. The surgeon excises said tissue for biopsy.

What is claimed is:
 1. A selective delivery molecule of Formula I,having the structure:[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I wherein, X isa cleavable linker; A is a peptide with a sequence comprising 5 to 9acidic amino acids; B is a peptide with a sequence comprising 7 to 9basic amino acids; c_(A), c_(B), and c_(M) are each independently 0-1amino acid; M is a polyethylene glycol (PEG) polymer; and D_(A) andD_(B) are each independently an imaging agent; and wherein [c_(M)-M] isbound to at any position on A or X, [D_(A)-c_(A)] is bound to any aminoacid on A, and [c_(B)-D_(B)] is bound to any amino acid on B.
 2. Themolecule of claim 1, wherein A and B do not have an equal number ofacidic and basic amino acids.
 3. The molecule of claim 2, wherein thenumber of basic amino acids in B is greater than the number of acidicamino acids in A.
 4. The molecule of claim 1, wherein A is a peptidecomprising 5 or 9 consecutive glutamates.
 5. The molecule of claim 1,wherein B is a peptide comprising 8 or 9 consecutive arginines.
 6. Themolecule of claim 1, wherein A is a peptide comprising 5 or 9consecutive glutamates and B is a peptide comprising 8 or 9 consecutivearginines.
 7. The molecule of claim 6, wherein A is a peptide comprising5 consecutive glutamates and B is a peptide comprising 8 consecutivearginines.
 8. The molecule of claim 1, wherein c_(A), c_(B), and c_(M)are each independently selected from a naturally-occurring amino acid ora non-naturally-occurring amino acid.
 9. The molecule of claim 8,wherein c_(A), c_(B), and c_(M) are each independently selected from a Damino acid, a L amino acid, an α-amino acid, a β-amino acid, or aγ-amino acid.
 10. The molecule of claim 1, wherein c_(A), c_(B), andc_(M) are each independently selected from any amino acid having a freethiol group, any amino acid having a N-terminal amine group, and anyamino acid with a side chain capable of forming an oxime or hydrazonebond upon reaction with a hydroxylamine or hydrazine group.
 11. Themolecule of claim 1, wherein c_(A), c_(B), and c_(M) are eachindependently selected from D-cysteine, D-glutamate, lysine, andpara-4-acetyl L-phenylalanine.
 12. The molecule of claim 10, whereinc_(B) is any amino acid having a free thiol group.
 13. The molecule ofclaim 12, wherein c_(B) is D-cysteine.
 14. The molecule of claim 10,wherein c_(A) is any amino acid having a N-terminal amine group.
 15. Themolecule of claim 14, wherein c_(A) is D-glutamate.
 16. The molecule ofclaim 1, wherein c_(A) is lysine.
 17. The molecule of claim 10, whereinc_(M) is any amino acid with a side chain capable of forming an oxime orhydrazone bond upon reaction with a hydroxylamine or hydrazine group.18. The molecule of claim 17, wherein c_(M) is para-4-acetylL-phenylalanine.
 19. The molecule of claim 1, wherein X is cleavable bya protease.
 20. The molecule of claim 19, wherein X is cleavable by amatrix metalloproteinase.
 21. The molecule of claim 20, wherein Xcomprises an amino acid sequence that is cleavable by MMP2, MMP7, MMP9,or MMP14.
 22. The molecule of claim 1, wherein X comprises a peptidelinkage.
 23. The molecule of claim 22, wherein X comprises an amino acidsequence selected from: PLGLAG, PLG-C(me)-AG, RPLALWRS, ESPAYYTA,DPRSFL, PPRSFL, RLQLKL, and RLQLK(Ac).
 24. The molecule of claim 23,wherein X comprises the amino acid sequence PLGLAG.
 25. The molecule ofclaim 23, wherein X comprises the amino acid sequence PLG-C(me)-AG. 26.The molecule of claim 23, wherein X comprises the amino acid sequenceRPLALWRS.
 27. The molecule of claim 23, wherein X comprises the aminoacid sequence DPRSFL.
 28. The molecule of claim 23, wherein X comprisesthe amino acid sequence PPRSFL.
 29. The molecule of claim 23, wherein Xcomprises the amino acid sequence RLQLKL.
 30. The molecule of claim 23,wherein X comprises the amino acid sequence RLQLK(Ac).
 31. The moleculeof any of claims 1-30, wherein D_(A) and D_(B) are a pair of acceptorand donor fluorescent moieties that are capable of undergoingFörsters/fluorescence resonance energy transfer with the other.
 32. Themolecule of claim 31, wherein D_(A) and D_(B) are Cy5 and Cy7.
 33. Themolecule of claim 31, wherein D_(A) and D_(B) are Cy5 and IRDye750. 34.The molecule of claim 31, wherein D_(A) and D_(B) are Cy5 and IRDye800.35. The molecule of claim 31, wherein D_(A) and D_(B) are Cy5 and ICG.36. The molecule of any of claims 1-30, wherein D_(A) and D_(B) are afluorescent moiety and a fluorescence-quenching moiety.
 37. The moleculeof claim 1, wherein the molecule of Formula I is: i) SDM-14 ii) SDM-15iii) SDM-23 iv) SDM-24 v) SDM-25 vi) SDM-26 vii) SDM-27 viii) SDM-32; orix) SDM-35.
 38. A molecule of Formula II, having the structure:A₁-X₁-B₁;   Formula II wherein, X₁ is a cleavable linker; A₁ is apeptide with a sequence comprising 5 to 9 acidic amino acids and havinga first reactive amino acid moiety c_(A); B₁ is a peptide with asequence comprising 7 to 9 basic amino acids and having a secondreactive amino acid moiety c_(B); and A₁-X₁-B₁ has a third reactiveamino acid moiety c_(M) on A₁ or X₁; and wherein c_(A) is capable ofreacting with a first cargo moiety comprising D_(A), c_(B) is capable ofreacting with a second cargo moiety comprising D_(B), and c_(M) iscapable of reacting with a macromolecular carrier comprising M to form amolecule of Formula I.
 39. The molecule of claim 38, wherein the c_(A),c_(B), and c_(M) have functional groups that are orthogonally reactive.40. The molecule of claim 38, wherein c_(A), c_(B), and c_(M) are eachindependently selected from a naturally-occurring amino acid or anon-naturally-occurring amino acid.
 41. The molecule of claim 38,wherein c_(A), c_(B), and c_(M) are each independently selected from a Damino acid, a L amino acid, an α-amino acid, a β-amino acid, or aγ-amino acid.
 42. The molecule of claim 38, wherein c_(A), c_(B), andc_(M) are each independently selected from any amino acid having a freethiol group, any amino acid having a N-terminal amine group, and anyamino acid with a side chain capable of forming an oxime or hydrazonebond upon reaction with a hydroxylamine or hydrazine group.
 43. Themolecule of claim 38, wherein c_(A), c_(B), and c_(M) are eachindependently selected from D-cysteine, D-glutamate, lysine, andpara-4-acetyl L-phenylalanine.
 44. The molecule of claim 42, whereinc_(B) is any amino acid having a free thiol group.
 45. The molecule ofclaim 44, wherein c_(B) is D-cysteine.
 46. The molecule of claim 42,wherein c_(A) is any amino acid having a N-terminal amine group.
 47. Themolecule of claim 46, wherein c_(A) is D-glutamate.
 48. The molecule ofclaim 38, wherein c_(A) is lysine.
 49. The molecule of claim 42, whereinc_(M) is any amino acid with a side chain capable of forming an oxime orhydrazone bond upon reaction with a hydroxylamine or hydrazine group.50. The molecule of claim 49, wherein c_(M) is para-4-acetylL-phenylalanine.
 51. A tissue sample comprising a molecule of Formula I:[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)];   Formula I wherein, Xis a cleavable linker; A is a peptide with a sequence comprising 5 to 9acidic amino acids; B is a peptide with a sequence comprising 7 to 9basic amino acids; c_(A), c_(B), and c_(M) are independently 0-1 aminoacid; M is a polyethylene glycol (PEG) polymer; and D_(A) and D_(B) areeach independently an imaging agent; and wherein [c_(M)-M] is bound atany position on A or X, [D_(A)-c_(A)] is bound to any amino acid on A,and [c_(B)-D_(B)] is bound to any amino acid on B.
 52. The tissue sampleof claim 51, wherein the tissue sample is a pathology slide or section.53. The tissue sample of claim 51, wherein the tissue sample iscancerous.
 54. The tissue sample of claim 53, wherein the canceroustissue is: breast cancer tissue, colon cancer tissue, squamous cellcarcinoma tissue, prostate cancer tissue, melanoma tissue, or thyroidcancer tissue.
 55. The tissue sample of claim 53, wherein the canceroustissue is breast cancer tissue.
 56. The tissue sample of claim 53,wherein the cancerous tissue is colon cancer tissue.
 57. The tissuesample of claim 51, wherein A and B do not have an equal number ofacidic and basic amino acids.
 58. The tissue sample of claim 57, whereinthe number of basic amino acids in B is greater than the number ofacidic amino acids in A.
 59. The tissue sample of claim 51, wherein A isa peptide comprising 5 or 9 consecutive glutamates.
 60. The tissuesample of claim 51, wherein B is a peptide comprising 8 or 9 consecutivearginines.
 61. The tissue sample of claim 51, wherein A is a peptidecomprising 5 or 9 consecutive glutamates and B is a peptide comprising 8or 9 consecutive arginines.
 62. The tissue sample of claim 61, wherein Ais a peptide comprising 5 consecutive glutamates and B is a peptidecomprising 8 consecutive arginines.
 63. The tissue sample of claim 51,wherein c_(A), c_(B), and c_(M) are each independently selected from anaturally-occurring amino acid or a non-naturally-occurring amino acid.64. The tissue sample of claim 63, wherein c_(A), c_(B), and c_(M) areeach independently selected from a D amino acid, a L amino acid, anα-amino acid, a β-amino acid, or a γ-amino acid.
 65. The tissue sampleof claim 51, wherein c_(A), c_(B), and c_(M) are each independentlyselected from any amino acid having a free thiol group, any amino acidhaving a N-terminal amine group, and any amino acid with a side chaincapable of forming an oxime or hydrazone bond upon reaction with ahydroxylamine or hydrazine group.
 66. The tissue sample of claim 51,wherein c_(A), c_(B), and c_(M) are each independently selected fromD-cysteine, D-glutamate, lysine, and para-4-acetyl L-phenylalanine. 67.The tissue sample of claim 65, wherein c_(B) is any amino acid having afree thiol group.
 68. The tissue sample of claim 67, wherein c_(B) isD-cysteine.
 69. The tissue sample of claim 65, wherein c_(A) is anyamino acid having a N-terminal amine group.
 70. The tissue sample ofclaim 69, wherein c_(A) is D-glutamate.
 71. The tissue sample of claim63, wherein c_(A) is lysine.
 72. The tissue sample of claim 65, whereinc_(M) is any amino acid with a side chain capable of forming an oxime orhydrazone bond upon reaction with a hydroxylamine or hydrazine group.73. The tissue sample of claim 72, wherein c_(M) is para-4-acetylL-phenylalanine.
 74. The tissue sample of claim 51, wherein X iscleavable by a protease.
 75. The tissue sample of claim 74, wherein X iscleavable by a matrix metalloproteinase.
 76. The tissue sample of claim75, wherein X comprises an amino acid sequence that is cleavable byMMP2, MMP7, MMP9, or MMP14.
 77. The tissue sample of claim 51, wherein Xcomprises a peptide linkage.
 78. The tissue sample of claim 77, whereinX comprises an amino acid sequence selected from: PLGLAG, PLG-C(me)-AG,RPLALWRS, ESPAYYTA, DPRSFL, PPRSFL, RLQLKL, and RLQLK(Ac).
 79. Thetissue sample of claim 77, wherein X comprises the amino acid sequencePLGLAG.
 80. The tissue sample of claim 77, wherein X comprises the aminoacid sequence PLG-C(me)-AG.
 81. The tissue sample of claim 77, wherein Xcomprises the amino acid sequence RPLALWRS.
 82. The tissue sample ofclaim 77, wherein X comprises the amino acid sequence DPRSFL.
 83. Thetissue sample of claim 77, wherein X comprises the amino acid sequencePPRSFL.
 84. The tissue sample of claim 77, wherein X comprises the aminoacid sequence RLQLKL.
 85. The tissue sample of claim 77, wherein Xcomprises the amino acid sequence RLQLK(Ac).
 86. The tissue sample ofany of claims 51-85, wherein D_(A) and D_(B) are a pair of acceptor anddonor fluorescent moieties that are capable of undergoingFörsters/fluorescence resonance energy transfer with the other.
 87. Thetissue sample of claim 86, wherein D_(A) and D_(B) are Cy5 and Cy7. 88.The tissue sample of claim 86, wherein D_(A) and D_(B) are Cy5 andIRDye750.
 89. The tissue sample of claim 86, wherein D_(A) and D_(B) areCy5 and IRDye800.
 90. The tissue sample of claim 86, wherein D_(A) andD_(B) are Cy5 and ICG.
 91. The tissue sample of any of claims 51-85,wherein D_(A) and D_(B) are a fluorescent moiety and afluorescence-quenching moiety.
 92. The tissue sample of claim 51,wherein the molecule of Formula I is: i) SDM-14 ii) SDM-15 iii) SDM-23iv) SDM-24 v) SDM-25 vi) SDM-26 vii) SDM-27 viii) SDM-32; and ix)SDM-35.
 93. A method of delivering a pair of imaging agents to a tissueof interest, comprising contacting the tissue of interest with amolecule of Formula I:[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)];   Formula I wherein, Xis a cleavable linker; A is a peptide with a sequence comprising 5 to 9acidic amino acids; B is a peptide with a sequence comprising 7 to 9basic amino acids; c_(A), c_(B), and c_(M) are independently 0-1 aminoacid; M is a polyethylene glycol (PEG) polymer; and D_(A) and D_(B) areeach independently an imaging agent; and wherein [c_(M)-M] is bound toat any position on A or X, [D_(A)-c_(A)] is bound to any amino acid onA, and [c_(B)-D_(B)] is bound to any amino acid on B.
 94. The method ofclaim 93, wherein the tissue of interest is cancerous.
 95. The method ofclaim 94, wherein the cancerous tissue is: breast cancer tissue,colorectal cancer tissue, squamous cell carcinoma tissue, prostatecancer tissue, melanoma tissue, and thyroid cancer tissue.
 96. Themethod of claim 94, wherein the cancerous tissue is breast cancertissue.
 97. The method of claim 94, wherein the cancerous tissue iscolon cancer tissue.
 98. The method of claim 93, wherein A and B do nothave an equal number of acidic and basic amino acids.
 99. The method ofclaim 93, wherein the number of basic amino acids in B is greater thanthe number of acidic amino acids in A.
 100. The method of claim 93,wherein A is a peptide comprising 5 or 9 consecutive glutamates. 101.The method of claim 93, wherein B is a peptide comprising 8 or 9consecutive arginines.
 102. The method of claim 93, wherein A is apeptide comprising 5 or 9 consecutive glutamates and B is a peptidecomprising 8 or 9 consecutive arginines.
 103. The method of claim 102,wherein A is a peptide comprising 5 consecutive glutamates and B is apeptide comprising 8 consecutive arginines.
 104. The method of claim 93,wherein c_(A), c_(B), and c_(M) are each independently selected from anaturally-occurring amino acid or a non-naturally-occurring amino acid.105. The method of claim 104, wherein c_(A), c_(B), and c_(M) are eachindependently selected from a D amino acid, a L amino acid, an α-aminoacid, a β-amino acid, or a γ-amino acid.
 106. The method of claim 93,wherein c_(A), c_(B), and c_(M) are each independently selected from anyamino acid having a free thiol group, any amino acid having a N-terminalamine group, and any amino acid with a side chain capable of forming anoxime or hydrazone bond upon reaction with a hydroxylamine or hydrazinegroup.
 107. The method of claim 93, wherein c_(A), c_(B), and c_(M) areeach independently selected from D-cysteine, D-glutamate, lysine, andpara-4-acetyl L-phenylalanine.
 108. The method of claim 106, whereinc_(B) is any amino acid having a free thiol group.
 109. The method ofclaim 108, wherein c_(B) is D-cysteine.
 110. The method of claim 106,wherein c_(A) is any amino acid having a N-terminal amine group. 111.The method of claim 110, wherein c_(A) is D-glutamate.
 112. The methodof claim 93, wherein c_(A) is lysine.
 113. The method of claim 106,wherein c_(M) is any amino acid with a side chain capable of forming anoxime or hydrazone bond upon reaction with a hydroxylamine or hydrazinegroup.
 114. The method of claim 113, wherein c_(M) is para-4-acetylL-phenylalanine.
 115. The method of claim 93, wherein X is cleavable bya protease.
 116. The method of claim 115, wherein X is cleavable by amatrix metalloproteinase.
 117. The method of claim 116, wherein Xcomprises an amino acid sequence that is cleavable by MMP2, MMP7, MMP9,or MMP14.
 118. The method of claim 93, wherein X comprises a peptidelinkage.
 119. The method of claim 118, wherein X comprises an amino acidsequence selected from: PLGLAG, PLG-C(me)-AG, RPLALWRS, ESPAYYTA,DPRSFL, PPRSFL, RLQLKL, and RLQLK(Ac).
 120. The method of claim 119,wherein X comprises the amino acid sequence PLGLAG.
 121. The method ofclaim 119, wherein X comprises the amino acid sequence PLG-C(me)-AG.122. The method of claim 119, wherein X comprises the amino acidsequence RPLALWRS.
 123. The method of claim 119, wherein X comprises theamino acid sequence DPRSFL.
 124. The method of claim 119, wherein Xcomprises the amino acid sequence PPRSFL.
 125. The method of claim 119,wherein X comprises the amino acid sequence RLQLKL.
 126. The method ofclaim 119, wherein X comprises the amino acid sequence RLQLK(Ac). 127.The method of any of claims 93-126, wherein D_(A) and D_(B) are a pairof acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother.
 128. The method of claim 127, wherein D_(A) and D_(B) are Cy5 andCy7.
 129. The method of claim 127, wherein D_(A) and D_(B) are Cy5 andIRDye750.
 130. The method of claim 127, wherein D_(A) and D_(B) are Cy5and IRDye800.
 131. The method of claim 127, wherein D_(A) and D_(B) areCy5 and ICG.
 132. The method of any of claims 93-126, wherein D_(A) andD_(B) are a fluorescent moiety and a fluorescence-quenching moiety. 133.The method of claim 93, wherein the molecule of Formula I is: i) SDM-14ii) SDM-15 iii) SDM-23 iv) SDM-24 v) SDM-25 vi) SDM-26 vii) SDM-27 viii)SDM-32; and ix) SDM-35.
 134. A method of visualizing a tissue ofinterest in an individual in need thereof, comprising: i) administeringto the individual a molecule of Formula I that localizes to the tissueof interest in the individual,[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)];   Formula I wherein, Xis a cleavable linker; A is a peptide with a sequence comprising 5 to 9acidic amino acids; B is a peptide with a sequence comprising 7 to 9basic amino acids; c_(A), c_(B), and c_(M) are independently 0-1 aminoacid; M is a polyethylene glycol (PEG) polymer; and D_(A) and D_(B) areeach independently an imaging agent; and wherein [c_(M)-M] is bound toat any position on A or X, [D_(A)-c_(A)] is bound to any amino acid onA, and [c_(B)-D_(B)] is bound to any amino acid on B; and ii)visualizing at least one of the imaging agents.
 135. The method of claim134, wherein the tissue is cancerous.
 136. The method of claim 135,wherein the cancerous tissue is: breast cancer tissue, colorectal cancertissue, squamous cell carcinoma tissue, prostate cancer tissue, melanomatissue, or thyroid cancer tissue.
 137. The method of claim 135, whereinthe cancerous cell or tissue is breast cancer tissue.
 138. The method ofclaim 135, wherein the cancerous cell or tissue is colon cancer tissue.139. The method of claim 134, further comprising surgically removing thetissue of interest from the individual.
 140. The method of claim 139,wherein the surgical margin surrounding the tissue of interest isdecreased.
 141. The method of claim 139, further comprising preparing atissue sample from the removed tissue of interest.
 142. The method ofclaim 134, further comprising staging the cancerous tissue.
 143. Themethod of claim 134, wherein A and B do not have an equal number ofacidic and basic amino acids.
 144. The method of claim 134, wherein thenumber of basic amino acids in B is greater than the number of acidicamino acids in A.
 145. The method of claim 134, wherein A is a peptidecomprising 5 or 9 consecutive glutamates.
 146. The method of claim 134,wherein B is a peptide comprising 8 or 9 consecutive arginines.
 147. Themethod of claim 134, wherein A is a peptide comprising 5 or 9consecutive glutamates and B is a peptide comprising 8 or 9 consecutivearginines.
 148. The method of claim 147, wherein A is a peptidecomprising 5 consecutive glutamates and B is a peptide comprising 8consecutive arginines.
 149. The method of claim 134, wherein c_(A),c_(B), and c_(M) are each independently selected from anaturally-occurring amino acid or a non-naturally-occurring amino acid.150. The method of claim 149, wherein c_(A), c_(B), and c_(M) are eachindependently selected from a D amino acid, a L amino acid, an α-aminoacid, a β-amino acid, or a γ-amino acid.
 151. The method of claim 134,wherein c_(A), c_(B), and c_(M) are each independently selected from anyamino acid having a free thiol group, any amino acid having a N-terminalamine group, and any amino acid with a side chain capable of forming anoxime or hydrazone bond upon reaction with a hydroxylamine or hydrazinegroup.
 152. The method of claim 134, wherein c_(A), c_(B), and c_(M) areeach independently selected from D-cysteine, D-glutamate, lysine, andpara-4-acetyl L-phenylalanine.
 153. The method of claim 151, whereinc_(B) is any amino acid having a free thiol group.
 154. The method ofclaim 153, wherein c_(B) is D-cysteine.
 155. The method of claim 151,wherein c_(A) is any amino acid having a N-terminal amine group. 156.The method of claim 155, wherein c_(A) is D-glutamate.
 157. The methodof claim 134, wherein c_(A) is lysine.
 158. The method of claim 151,wherein c_(M) is any amino acid with a side chain capable of forming anoxime or hydrazone bond upon reaction with a hydroxylamine or hydrazinegroup.
 159. The method of claim 158, wherein c_(M) is para-4-acetylL-phenylalanine.
 160. The method of claim 134, wherein X is cleavable bya protease.
 161. The method of claim 160, wherein X is cleavable by amatrix metalloproteinase.
 162. The method of claim 161, wherein Xcomprises an amino acid sequence that is cleavable by MMP2, MMP7, MMP9,or MMP14.
 163. The method of claim 134, wherein X comprises a peptidelinkage.
 164. The method of claim 163, wherein X comprises an amino acidsequence selected from: PLGLAG, PLG-C(me)-AG, RPLALWRS, ESPAYYTA,DPRSFL, PPRSFL, RLQLKL, and RLQLK(Ac).
 165. The method of claim 164,wherein X comprises the amino acid sequence PLGLAG.
 166. The method ofclaim 164, wherein X comprises the amino acid sequence PLG-C(me)-AG.167. The method of claim 164, wherein X comprises the amino acidsequence RPLALWRS.
 168. The method of claim 164, wherein X comprises theamino acid sequence DPRSFL.
 169. The method of claim 164, wherein Xcomprises the amino acid sequence PPRSFL.
 170. The method of claim 164,wherein X comprises the amino acid sequence RLQLKL.
 171. The method ofclaim 164, wherein X comprises the amino acid sequence RLQLK(Ac). 172.The method of any of claims 134-171, wherein D_(A) and D_(B) are a pairof acceptor and donor fluorescent moieties that are capable ofundergoing Försters/fluorescence resonance energy transfer with theother.
 173. The method of claim 172, wherein D_(A) and D_(B) are Cy5 andCy7.
 174. The method of claim 172, wherein D_(A) and D_(B) are Cy5 andIRDye750.
 175. The method of claim 172, wherein D_(A) and D_(B) are Cy5and IRDye800.
 176. The method of claim 172, wherein D_(A) and D_(B) areCy5 and ICG.
 177. The method of claim 172, further comprisingvisualizing Försters/fluorescence resonance energy transfer betweenD_(A) and D_(B).
 178. The method of any of claim 134-171, wherein D_(A)and D_(B) are a fluorescent moiety and a fluorescence-quenching moiety.179. The method of claim 134, wherein the molecule is chosen from: i)SDM-14 ii) SDM-15 iii) SDM-23 iv) SDM-24 v) SDM-25 vi) SDM-26 vii)SDM-27 viii) SDM-32; and ix) SDM-35.
 180. A selective delivery moleculeof Formula I, having the structure:[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I wherein, X isa peptide linker cleavable by a matrix metalloproteinase; A is a peptidewith a sequence comprising 5 or 9 consecutive glutamates; B is a peptidewith a sequence comprising 8 or 9 consecutive arginines; c_(A), c_(B),and c_(M) are each independently an amino acid; M is a polyethyleneglycol (PEG) polymer; and D_(A) and D_(B) are a pair of acceptor anddonor fluorescent moieties that are capable of undergoingFörsters/fluorescence resonance energy transfer with the other; andwherein [c_(M)-M] is bound to at any position on A or X, [D_(A)-c_(A)]is bound to any amino acid on A, and [c_(B)-D_(B)] is bound to any aminoacid on B.
 181. The molecule of claim 180, wherein A and B do not havean equal number of acidic and basic amino acids.
 182. The molecule ofclaim 180, wherein c_(A), c_(B), and c_(M) are each independentlyselected from any amino acid having a free thiol group, any amino acidhaving a N-terminal amine group, and any amino acid with a side chaincapable of forming an oxime or hydrazone bond upon reaction with ahydroxylamine or hydrazine group.
 183. The molecule of claim 180,wherein c_(A), c_(B), and c_(M) are each independently selected fromD-cysteine, D-glutamate, lysine, and para-4-acetyl L-phenylalanine. 184.The molecule of claim 182, wherein c_(B) is any amino acid having a freethiol group.
 185. The molecule of claim 184, wherein c_(B) isD-cysteine.
 186. The molecule of claim 182, wherein c_(A) is any aminoacid having a N-terminal amine group.
 187. The molecule of claim 186,wherein c_(A) is D-glutamate.
 188. The molecule of claim 182, whereinc_(M) is any amino acid with a side chain capable of forming an oxime orhydrazone bond upon reaction with a hydroxylamine or hydrazine group.189. The molecule of claim 188, wherein c_(M) is para-4-acetylL-phenylalanine.
 190. The molecule of claim 180, wherein X comprises theamino acid sequence PLGLAG.
 191. The molecule of claim 180, wherein Xcomprises the amino acid sequence PLG-C(me)-AG.
 192. The molecule ofclaim 180, wherein X comprises the amino acid sequence RPLALWRS. 193.The molecule of any of claims 180-192, wherein D_(A) and D_(B) are Cy5and Cy7.
 194. The molecule of any of claims 180-192, wherein D_(A) andD_(B) are Cy5 and IRDye750.
 195. The molecule of any of claims 180-192,wherein D_(A) and D_(B) are Cy5 and IRDye800.
 196. The molecule of anyof claims 180-192, wherein D_(A) and D_(B) are Cy5 and ICG.
 197. Aselective delivery molecule of Formula I, having the structure:[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I wherein, X isa peptide linker cleavable by a matrix metalloproteinase; A is a peptidewith a sequence comprising 5 consecutive glutamates; B is a peptide witha sequence comprising 8 consecutive arginines; c_(A), c_(B), and c_(M)are each independently an amino acid; M is a polyethylene glycol (PEG)polymer; and D_(A) and D_(B) are a pair of acceptor and donorfluorescent moieties that are capable of undergoingFörsters/fluorescence resonance energy transfer with the other; andwherein [c_(M)-M] is bound to at any position on A or X, [D_(A)-c_(A)]is bound to any amino acid on A, and [c_(B)-D_(B)] is bound to any aminoacid on B.
 198. The method of claim 197, wherein c_(A), c_(B), and c_(M)are each independently selected from any amino acid having a free thiolgroup, any amino acid having a N-terminal amine group, and any aminoacid with a side chain capable of forming an oxime or hydrazone bondupon reaction with a hydroxylamine or hydrazine group.
 199. The methodof claim 197, wherein c_(A), c_(B), and c_(M) are each independentlyselected from D-cysteine, D-glutamate, lysine, and para-4-acetylL-phenylalanine.
 200. The method of claim 197, wherein c_(B) is anyamino acid having a free thiol group.
 201. The method of claim 200,wherein c_(B) is D-cysteine.
 202. The method of claim 197, wherein c_(A)is any amino acid having a N-terminal amine group.
 203. The method ofclaim 202, wherein c_(A) is D-glutamate.
 204. The method of claim 197,wherein c_(M) is any amino acid with a side chain capable of forming anoxime or hydrazone bond upon reaction with a hydroxylamine or hydrazinegroup.
 205. The tissue sample of claim 204, wherein c_(M) ispara-4-acetyl L-phenylalanine.
 206. The molecule of claim 197, wherein Xcomprises the amino acid sequence PLGLAG.
 207. The molecule of claim197, wherein X comprises the amino acid sequence PLG-C(me)-AG.
 208. Themolecule of claim 197, wherein X comprises the amino acid sequenceRPLALWRS.
 209. The molecule of any of claims 197-208, wherein D_(A) andD_(B) are Cy5 and Cy7.
 210. The molecule of any of claims 197-208,wherein D_(A) and D_(B) are Cy5 and IRDye750.
 211. The molecule of anyof claims 197-208, wherein D_(A) and D_(B) are Cy5 and IRDye800. 212.The molecule of any of claims 197-208, wherein D_(A) and D_(B) are Cy5and ICG.
 213. A selective delivery molecule of Formula I, having thestructure:[D_(A)-c _(A)]-A-[c _(M)-M]-X-B-[c _(B)-D_(B)]   Formula I wherein, X isa peptide linker cleavable by a matrix metalloproteinase; A is a peptidewith a sequence comprising 9 consecutive glutamates; B is a peptide witha sequence comprising 9 consecutive arginines; c_(A), c_(B), and c_(M)are each independently an amino acid; M is a polyethylene glycol (PEG)polymer; and D_(A) and D_(B) are a pair of acceptor and donorfluorescent moieties that are capable of undergoingFörsters/fluorescence resonance energy transfer with the other; andwherein [c_(M)-M] is bound to at any position on A or X, [D_(A)-c_(A)]is bound to any amino acid on A, and [c_(B)-D_(B)] is bound to any aminoacid on B.
 214. The method of claim 213, wherein c_(A), c_(B), and c_(M)are each independently selected from any amino acid having a free thiolgroup, any amino acid having a N-terminal amine group, and any aminoacid with a side chain capable of forming an oxime or hydrazone bondupon reaction with a hydroxylamine or hydrazine group.
 215. The methodof claim 213, wherein c_(A), c_(B), and c_(M) are each independentlyselected from D-cysteine, D-glutamate, lysine, and para-4-acetylL-phenylalanine.
 216. The method of claim 213, wherein c_(B) is anyamino acid having a free thiol group.
 217. The method of claim 216,wherein c_(B) is D-cysteine.
 218. The method of claim 213, wherein c_(A)is any amino acid having a N-terminal amine group.
 219. The method ofclaim 218, wherein c_(A) is D-glutamate.
 220. The method of claim 213,wherein c_(M) is any amino acid with a side chain capable of forming anoxime or hydrazone bond upon reaction with a hydroxylamine or hydrazinegroup.
 221. The tissue sample of claim 220, wherein c_(M) ispara-4-acetyl L-phenylalanine.
 222. The molecule of claim 213, wherein Xcomprises the amino acid sequence PLGLAG.
 223. The molecule of claim213, wherein X comprises the amino acid sequence PLG-C(me)-AG.
 224. Themolecule of claim 213, wherein X comprises the amino acid sequenceRPLALWRS.
 225. The molecule of any of claims 213-224, wherein D_(A) andD_(B) are Cy5 and Cy7.
 226. The molecule of any of claims 213-224,wherein D_(A) and D_(B) are Cy5 and IRDye750.
 227. The molecule of anyof claims 213-224, wherein D_(A) and D_(B) are Cy5 and IRDye800. 228.The molecule of any of claims 213-224, wherein D_(A) and D_(B) are Cy5and ICG.
 229. A selective delivery molecule according to SDM-14.
 230. Aselective delivery molecule according to SDM-15.
 231. A selectivedelivery molecule according to SDM-23.
 232. A selective deliverymolecule according to SDM-24.
 233. A selective delivery moleculeaccording to SDM-25.
 234. A selective delivery molecule according toSDM-26.
 235. A selective delivery molecule according to SDM-27.
 236. Aselective delivery molecule according to SDM-32.
 237. A selectivedelivery molecule according to SDM-35.
 238. A peptide according toPeptide P-3.